Two Lines, No Waiting

"Grandson: Grandpa, is this the same story?

Klaus: No, this is a little side-story. I'm using it to break up the main story so you don't get bored.

Grandson: Are we part of the story?

Klaus: Oh, no. We are a Framing Device."

- American Dad

Two narrative threads -- or more -- are woven together; two cases are prosecuted, two murders investigated, and so on. This allows a simple narrative structure to feel as if it has more variety. It gives the audience a break from one line and something to do in terms of recalling the events of the alternate line. The two stories may be about similar subjects, or one may be the usual fare (investigations, prosecutions) interleaved with character development that gives a sense of a Story Arc. Crime shows or films often feature parallel stories whose heroes turn out to be Working the Same Case.

Juggling two stories is common enough that writers frequently refer to the "A Story" and the "B Story." Three or more is quite a bit less common, at least in purely episodic or limited-continuity shows.

If the B Story is clearly subservient to the A Story, it will usually be described as the "subplot". A common pattern on many series - and sitcoms in particular - is that the same sets of characters will usually be segregated into "main plot" and "subplot" every week.

In Arc-heavy fare, two or three recurring storylines may be hit along with one or two minor "breather" plotlines all at once. This just means less screen time for each plotline, which mean they all go on for more episodes, which means the viewers keep watching. This is common in Soaps, long-form dramas, and some Sci Fi series.

If the A Story and B Story aren't juggled simultaneously, but are instead handled separately and tied together with an incredible chain of events, it's Halfway Plot Switch. If said chain of events is split over two time periods, it's Meanwhile in the Future. Often uses Plot Parallels to set up a Double Aesop.

For a Soap Opera variation see Soap Wheel and Four Lines, All Waiting. Contrast Offstage Waiting Room. If one of the storylines seems utterly inconsequential compared to the other, you may have a case of Trapped by Mountain Lions. When a battle is starting in one storyline and the camera switches to another storyline, this is an example of a Charge Into Combat Cut. See also Simultaneous Arcs, when the entirety of one arc is told before the next one gets told, but each one happens at the same time.

Anime

 * Baccano. Oh, Baccano. There are three main stories, each taking place a year apart. (1930, 1931, 1932) Also, one in the 1700s. The clips from each of these are then mixed together throughout each episode, and you don't get to see the end of any of them until you finish the series. It's slightly less confusing than it sounds, the clips usually begin by stating the year in which they occur. Usually. And those aren't even counting the flashbacks.
 * An episode of Yu-Gi-Oh! from early season 2 had gone through this in the form of a Day in The Limelight episode. The A Story focused on Kaiba learning about his and Yugi's collective pasts in Ancient Egypt, while the B story focused on Yugi lamenting about his near-death experience in the previous episode, fearing that he would lose his other self forever (or in the dub, feeling anxious about facing Marik).
 * The rest of Season 2 qualifies as well, with the A Story being Yugi facing the Rare Hunters and uncovering Marik's plan, while the B Story focuses on Joey coming into his own as a duelist without Yugi's help. The two plots converge when Marik has Joey kidnapped and mind-controlled to duel Yugi.
 * Naruto has an odd variation of this. It started as one plot, but when Sasuke jumps ship, the plot diverges into two main streams (with a third one that's mostly disconnected until recently when they've decided to taper back into one.
 * Legend of Galactic Heroes switches rapidly between two interplanetary superpowers and how individuals from both interact and how those interactions influence other interactions and so on.
 * The first half of Transformers Cybertron deftly juggled three plot threads at once, varying the focus each one received. The first introduced was the search for the Omega Lock on Earth. After a few episodes, they discovered the location of the first Cyber Planet Key on Velocitron, which led to a secondary thread about Hot Shot and Red Alert competing in a series of races to try and win it. Some time later, a third thread was introduced when the second Key was traced to Jungle Planet, and Overhaul was sent to retrieve it from Scourge. Meanwhile, the Omega Lock was found, the race was won, and finally Scourge defeated, leading up to the more linear but still exciting second half of the series.
 * Fullmetal Alchemist is widely praised for this. Usually Ed and Al are followed in one plotline while Roy and his troops are followed in the second, but there are also tertiary plotlines about Scar, Winry and others.
 * The Pokémon Best Wishes anime series has done this, with the Team Rocket trio occasionally stopping their usual pursuit of Ash's group and instead operating a long-term mission elsewhere. Their plotline progresses while Ash's does, and eventually the two merge together for a finish.
 * To Aru Majutsu no Index has Touma, Accelerator, and Shiage having their own crazy adventures in Academy City and later Russia. Volume 1 of "New Testament" is the first time all three of them meet at the same time.

Comics

 * Fifty Two was an enormous critical and financial success as it utilized at least seven lines with no waiting. Featuring several different "main" characters, each character had their own plot throughout the series which would occasionally cross over into other characters plot-lines. These stories ranged from personal, character-driven issues (Such as Ralph Dibny's personal quest to bring his wife back from the dead) to large-scale, grandiose events (Like Black Adam's alliance with, and then struggle against, superpowered groups throughout the world), and some were not connected to the other stories in any way (Like Animal Man, Starfire, and Adam Strange struggling to get back to Earth from across the galaxy). One of the points credited to Fifty Two's success was its ability to make all these unconnected stories mesh together and complement one another, avoiding Four Lines, All Waiting.
 * Unfortunately, its follow-up was...not so tightly crafted.
 * A Finnish comic novel named "OM" did this in a decidedly MindScrewy way. The A Story (or at least the one it opened on), being the adventures of the eponymous samurai rabbit, was interrupted abruptly by the B Story of the surreal Just for Pun adventures of "li'l Piggybear". The B Story, in turn, was ostensibly the dreams of one of the characters in the C Story, a real-world relationship drama. The connection (if any) between the stories was never in any adequate way explained, giving the comic an overarching "what the... ?" -kind of feel. Ostensibly, the C Story, which was introduced last, could be seen as the "main" story, but that is all open to interpretation... It could just as well have been All Just a Dream of the samurai protagonist who was, if memory serves correctly, mortally wounded at the time.

Fan Works

 * With Strings Attached tells two parallel stories: that of the four and their adventures on a variety of worlds, and that of the Fans who put them in this situation and who are watching/commenting on/empowering/manipulating them. The two lines are semi-separate (the Fans are aware of the four, but not vice-versa) until the end of the Second Movement, when the Fans speak directly to the four for the first time. The threads intersect a few more times in the book but mostly remain separate.
 * There are also several chapters, notably the New Zork chapter, where the four get split up and have individual adventures, or which focus on only one of the four.

Film

 * Movie examples abound, but 2006's The Holiday stands out because either of the two plots could have stood alone as a mildly-amusing single-story film.
 * Another movie example: For most of Star Wars: The Empire Strikes Back, the film follows two separate storylines, one devoted to Luke learning the ways of the Jedi from Yoda and the other devoted to Han and Leia's attempts to evade the Empire. Attack of the Clones, the second installment of the prequel trilogy, also followed this structure. It followed Obi Wan on the search for the bounty hunter that hired an assassin to kill Padme, and it followed Padme and Anakin on the romantic plot as well as the search for his mother.
 * Pan's Labyrinth had the "Ofelia's Tasks" plot and the "Resistance Against Fascists" plot, which intersected towards the end because the head of said fascists is Ofelia's step-father.
 * The second and third movies in The Lord of the Rings trilogy. The original books interlaced two narrative strands in the first half of each volume, but the third strand separate. This didn't work so well on film, so Peter Jackson cut them up, interlacing all three.
 * All of the movies in the Saw series (except the first) fit this structure. Line A is mostly about the plot/suspense, while Line B is more about Gorn. The movie jumps to Line A whenever something Gorntastic happens in Line B. It jumps to Line B after some plot development resolves in Line A. Some of the movies spend more time in Line A (Saw V) and some spend more time in Line B (Saw III), which directly relates to how gorey a given installment is. These plots always meet up in some fashion at the end.
 * Requiem for a Dream does this. The four stories are initially linked as the girlfriend, friend, and mother of Jared Leto's character, although they all eventually branch off into their own, primarily unrelated tales. They are still somewhat linked, but for the most part they've gone their own ways.
 * Woody Allen has done these a few times in two of his highest regarded movies. Crimes And Misdemeanors has a straight example with the two storylines being distinct and only crossing paths rarely, while Hannah and Her Sisters follows several character arcs with a lot of interaction between them.

Literature

 * The book Sahara by Clive Cussler (and its movie adaption that he has disowned) has two plots running side by side, interlinking with each other. It eventually then focuses exclusively on one, with the other only coming back just when the audience has forgotten about it.
 * The Kurt Austin series of the Clive Cussler books do this. Kurt Austin and Joe Zavala are plot A, Paul Trout and his wife Gamay Morgan-Trout are Plot B. Then because of various reasons there will be parts where Austin will work with Trout while Zavala and Gamay work together. Which gets humorous when Kurt and Paul have to sneak around because Trout is nearly 7-feet tall.
 * Most Redwall novels involve multiple, interwoven plots. Salamandastron is possibly the most convoluted in this respect.
 * Terry Brooks almost always does this in his Shannara books, when the parties split. Normally one half fights some epic but largely mundane battle, while the other party (with the main protagonist) goes off to kill the Big Bad. This is probably in deliberate imitation of LOTR.
 * Several Discworld novels feature two parallel plotlines that occasionally interact, finally uniting near the end, for example Reaper Man (Death's retirement and Windle Poons's "afterlife", with slightly different typefaces to distinguish them) and Hogfather (Death taking the Hogfather's role; Susan stopping Teatime).
 * The Mind Screw book Kafka on the Shore features two completely different stories alternating every chapter. The odd numbered chapters have a mostly realistic (at least until the end) story of a teenage runaway, and the even numbered ones are about a guy who can talk to cats and is convinced he has to fulfill some destiny to keep evil from taking over the world. The two stories impact on each other from time to time without ever quite intersecting.
 * Author Haruki Murakami is good at this. His earlier novel Hard-Boiled Wonderland and the End of the World was, as the title suggests, two separate stories. One is a cyberpunk neo-noir thriller (Wonderland) and the other is a magical fantasy (End of the World). The two stories have the same protagonist, though - and they can't both have happy endings.
 * Neal Stephenson is especially fond of this trope. Nearly all of them feature at least 2 plots, although they always intersect by the end.
 * Cryptonomicon, for example, has a plot following Lawrence Waterhouse and Alan Turing breaking Axis cyphers in 1942, Bobby Shaftoe in service at the Navy around the same years, and Randy Waterhouse setting up a business operation in the present.
 * The Confusion deserves special mention for being presented as two separate novels mixed (or "confused") together (the other volumes in The Baroque Cycle contain three books, but present them one at a time). Both novels have a couple of strands to them.
 * Snow Crash has Hiro Protagonist and YT as major viewpoint characters. They work together and spend much of their time together, but during the story have completely separate conflicts. It turns out that they are heading towards the same plot climax, but from two completely different directions.
 * Literary example: The Wheel of Time the later books fragment into several plotlines. This either creates a vivid, appealing world or makes the books hopelessly convoluted, depending on the reader.
 * A Song of Ice and Fire is a particularly strong example of it. In the first book, it starts with three plots - basically one following Eddard Stark, one following Jon Snow, and the third following Daenerys. Over the course of the first book the characters end up getting really spread out and by the second book there are a huge number of interwoven plots, plus Daenerys who has spawned no other point of view characters and has really had minimal interaction with the rest of the cast. The plot is incredibly convoluted with dozens of characters and more than a dozen different point of view characters. Of course, given that Daenerys has gotten so much time, and yet is on the other side of an ocean, we all know something very important is going to happen with her in the last book...
 * Daenerys is an odd example, because the actions the characters on Westeros actually have a constant impact on her life--it just sometimes takes a while to cross the ocean and get to her. The first example that springs to mind would be the time.
 * It looks like Dany might be moving into the main plotline, or the main plotline might be moving to Daenerys--preview chapters from the next book strongly indicate that she'll be joining forces with in the future.
 * Mercedes Lackey - in her Mage Storms trilogy, the main plot gets interwoven with machiavellian scheming in a distant and uber-powerful empire. The B plot gives the readers insight into one of the major characters as well as answering several questions that any smart reader would be asking and couldn't be properly answered any other way.
 * Same with The Obsidian Trilogy, which has the main plot with the main characters and another equally important plot happening back in the city.
 * Peter F. Hamilton does this quite a bit. His Commonwealth Saga follows something like seven plots all at once, and they'd each be enough for a book of their own. The Nights Dawn Trilogy has three major plots going at once. There's a reason his books are so thick.
 * Malazan Book of the Fallen does this with around 4-5 lines. Book 2 and 3 even happened at exactly the same time.
 * Sandy Mitchell's Warhammer 40000 novel Scourge The Heretic breaks into two infiltration plots: One for the smugglers, one for the Chaos cult.
 * The defining characteristic of the Victorian multiplot novel. For example:
 * Wilkie Collins, The Woman in White
 * W. M. Thackeray, Vanity Fair
 * George Eliot, Daniel Deronda and Middlemarch (more than two in the latter).
 * Charles Dickens, Bleak House
 * Anthony Trollope, The Way We Live Now and most of his other novels
 * After Fellowship, The Lord of the Rings breaks down into two stories for most of its run: Frodo and Sam, and the rest of the Fellowship. Even then, there are sub-divisions in the rest of the Fellowship for a good deal of the time, such as the two views of the march of the Uruk-hai - one from Merry and Pippin, the other from Aragorn, Legolas, and Gimli.
 * The early parts of Return of the King fragment this a little more, as we get separate views on Pippin and Gandalf in Minas Tirith, Merry with the Rohirrim, and Aragorn, Legolas, and Gimli on the Paths of the Dead. All this is in addition to Frodo and Sam's part of the story, which eventually leads to the re-merging of the disparate threads.
 * The Swallows and Amazons series of children's novels by Arthur Ransome follows several families of children who only meet in their school holidays. After the fifth book in the series (Coot Club), there are often two plots running concurrently in different novels, and the characters even send postcards to friends who don't appear. The thirteenth book would have united characters who had never met, but Ransome never finished it.
 * The latter half of Dark Lord of Derkholm ping-pongs between the adventures of Derk and those of his children, Blade, Shona, and Kit, as they lead a party through the "game."
 * Older Than Feudalism: The Odyssey has Odysseus attempting to get home, and Odysseus's son Telemachos's attempts to find his father.
 * In Mike Lee's Warhammer 40000 Horus Heresy novel Fallen Angels, Nemiel's and Zahariel's stories.
 * Timothy Zahn does this all the time in his Star Wars Expanded Universe novels. All of his many protagonists have plotlines that weave and diverge and intersect and merge constantly. In Allegiance, chosen for an example because it has a smaller cast, the plotlines belong to Mara Jade and her mission to follow a pirate/corrupt Imperial connection, Daric LaRone and the Hand of Judgment with their efforts to do good and figure out what to do next, Luke Skywalker and Han Solo fumbling with Han's reservations about the Rebellion while on a mission, Leia Organa and her quest to keep bits of the Rebellion together, Villim Disra's gambit to get more power, and Captain Ozzel with his increasingly desperate attempts to hide the fact that five stormtroopers defected from his ship. And all of these plotlines forms its own narrative, but is related somehow to all of the others. They rarely get forgotten, either. Zahn's awesome like that.
 * This is done less impressively in the multi-author Fate of the Jedi series. It's loosely based on The Odyssey, with Luke and his son exploring strange places and meeting exotic force-using organizations. But, there's also a murder trial, a power struggle between the government and the Jedi Order, a conspiracy right out of Shakespeare's Julius Caesar, a little girl Chosen One who gets into trouble, and a big sub-plot about slavery. Each book shows some Jedi falling into a paranoid psychosis and causing trouble. Can you remember all of these?... Well, the authors have ignored the investigation into Jacen for a new plot involving an Eldritch Abomination for several books (though they still visit strange places/groups), and a group of Jedi got sent out to fight slavery, only to be ignored the next book.
 * Holes, by Louis Sachar, alternates between the story of Stanley Yelnats' life at Camp Green Lake, the story of Stanley's "pig-stealing" great-great-grandfather Elya, and the story of schoolteacher Kate Barlow in the Old West town of Green Lake and how she became a feared outlaw. The connections between the three stories become ever clearer throughout the book.
 * Brandon Sanderson's Mistborn series. The first book starts with Kelsier, Vin, and Elend as viewpoint characters. When their plots diverge, each of them tends to be given a chapter at a time, which helps things move smoothly along. The even spread of viewpoints chapter-by-chapter becomes very noticeable by book three when several secondary characters have become viewpoint characters and they all have their own plots.
 * It' SOP for Nancy Drew books to start with two seemingly unrelated mysteries that turn out to be the same thing by the end of the story.
 * Same for the Hardy Boys.
 * Leviathan, by Scott Westerfeld, has two plots like this. The first tells of Aleksandar Ferdinand, who is on the run after the assassination of his father, Franz Ferdinand. The second is about Deryn Sharp, a girl who dresses like a boy to get into the British Air Service. About 2/3 through the book, their two stories intersect when.
 * Ken MacLeod has used this, most notably in The Sky Road and The Stone Canal. He was also credited by his friend Iain Banks for suggesting it as a way of bringing together the various Culture-related ideas and storylines that became Use Of Weapons.
 * The story in Nick Hornby's About a Boy is told alternately by the two Protagonists, at the beginning of the book both plots are separated, as the story proceeds they get somewhat mixed up a little, owing to the time they spend together.
 * Interworld gets a bit weird about this. The book is divided into two halves. The first half is about a guy by the name of Tom Dunjer searching for a sample of something called linzetium, which has been stolen. It's mostly pretty sensibly laid out, except that at the end of each chapter, there's a section in ALL CAPS from the point of view of Klox, a robot who starts off not knowing where he is or what he's doing. At some point in the second half, Dunjer meets Klox. After that, chapters start alternating between those following Dunjer, and some written in italics, told from the point of view of another Dunjer in a Parallel Universe. Both the Dunjer and alt-Dunjer chapters still include the Klox sections at the end. The final chapter constantly switches between the Dunjer and alt-Dunjer sections, with the Klox section running along on another trajectory which intersects with both.
 * Ragtime features three families living in the early 20th century. While each has its own story ranging from following the American Dream to avenging your baby mama's death through terrorism to adjusting to the New Music, they find themselves interacting to an almost ridiculous degree, in an amount of detail that would make JRR Tolkien envious. At the end the surviving main characters become one family.
 * Several of Jane Austen's novels have this.
 * Sense and Sensibility has Elinor and Marianne as the main characters. Each sister has her own plot.
 * Eastern Standard Tribe has two converging storylines that mix with How We Got Here.
 * In Robert E. Howard's Conan the Barbarian story "A Witch Shall Be Born", Valerius and La Résistance; Conan himself; and Salome, the Big Bad.
 * Ian Irvine's Three Worlds Cycle does this regularly. The first book, A Shadow On The Glass, opens with two separate plot threads from Karan and Llian, which later converge, and over the course of the quartet the action often switches between different characters in different places, who tend to come together for the final events of each book only to separate again in the next one. It all comes to a head with the third series, the Song Of The Tears trilogy, where all the keysurvivng players from the entire series join forces to deal with the overarching threat.
 * Extremely Loud and Incredibly Close alternates between Oskar's journey to cope with his father's death and letters from Oskar's grandparents detailing how they met and their eventual separation.
 * Spider Robinson's Mindkiller has two plotlines, told in alternating chapters -- odd-numbered chapters are in third-person, through the eyes of college professor Norman Kent, and even-numbered chapters are told in first-person by Army-vet-turned-techie-burglar Joe Templeton. It's not until at least two-thirds of the way through the story that it's made explicit that
 * For the the first two books of The New Prophecy, the second arc of Warrior Cats, the point of view switches between Leafpaw, a medicine cat apprentice watching as the forest crumbles around her, and one of the six journeying cats, who are on a quest to find a way to save the forest.

Live Action TV
"Dr. Cox: What in the hell are you talking about?
 * Perfected by 24. After all, it is the Trope Namer for Trapped by Mountain Lions.
 * The most obvious examples would have to be Fantasy Island and The Love Boat, each of which juggled three or more plotlines per episode. In fact, the plotlines even had separate titles in the credits, and usually different writers!
 * This device is used in the various CSI shows (although much more often in the original than the spinoffs), and others in the current crop.
 * Occasionally the characters will find out halfway through the episode that the crimes they are investigating are tied together. Some episodes pull this off better than others.
 * This happens pretty often in New Tricks. Sandra normally goes off with one other member of the team about a quarter through the episode, with the other two members going off on their own plotline as well. Sometimes there are even three plotlines in one episode.
 * House often has this (particularly in the last few seasons), where plot A is the current medical drama and there's usually one or two sub-plots concerning House messing with his team and/or Wilson and/or Cuddy (or vice versa).
 * Very common in Star Trek spin-offs. Star Trek: The Next Generation's early seasons suffered badly from a sense that the writers felt obligated to have multiple plotlines, and events that should have been the centerpiece of an entire episode were relegated to the B Story (e.g., the re-introduction of the Romulans).
 * The most Egregious example coming from a Star Trek: Enterprise episode "Silent Enemy." The A plot is a strong, tense plot where the Enterprise is face with an enemy that outclasses their ship in every way. The ship is boarded, lives are lost, and in order to even survive, the Enterprise has to risk blowing half the ship apart. The B plot is centered around Hoshi finding out Reed's favorite food. Hilarity Ensues, despite, you know, the ship endangering crisis going on. Needless to say, the A plot is horribly undermined by the thematic discontinuity, and gross stupidity, of the B plot.
 * This structure was used in basically every episode of Star Trek: Deep Space Nine, with the notable exception of the late-first-season episode "Duet".
 * Also used in the movie Star Trek: First Contact. Oddly, the movie's title came from the "B" plot.
 * Babylon 5 did this in just about every single episode.
 * On occasion, you could count all the way down to an 'F' plot.
 * Most episodes stuck with the 'A' plot (the main story being presented in that episode), the 'B' plot (a continuation of one of the main story arcs) and sometimes (but not always) a 'C' plot (usually comedy relief).
 * Word of God is A Arc is the Series story, the 5 of which linked to make the complete story, B Arc, one that ran for a few episodes, contributing towards the A arc, and the C arc, the episode arc - 'this weeks story'. Its basically a really well plotted RPG campaign.
 * This trope was so prevalent on the show that episodes with only one plot line really stand out. One big example is the fourth season episode "Intersections in Real Time," which focused exclusively on Sheridan
 * The new Battlestar Galactica Reimagined series always has at least three storylines, and sometimes as many as five.
 * Lizzie McGuire consistently used Lizzie and her friends as the "A" Story, and her little brother Matt doing something for the "B" Story.
 * For that matter; pretty much every episode of every sit-com on Disney Channel does this.
 * Shake It Up. Usually there is one plot with Cece and Rocky, and Rocky's brother Ty, Deuce and Flynn have a plot. They may or may not intersect, and minor character Gunther and Tinka may appear in both.
 * Hannah Montana: Lilly/Hannah in the A-Plot, Jackson and/or Rico in the B-Plot. Oliver and Robbie Ray can be in one or both.
 * Good Luck Charlie: Teddy and Ivy in the A-Plot. PJ, Gabe or Bob in the B-Plot.
 * Wizards of Waverly Place has Alex and Harper and Justin in the A-plot, and Max and the parents in the B-plot.
 * The Suite Life of Zack and Cody have Zack and Cody in the A-plot, and London and Maddie in the B-plot. London and Bailey are in the B-plot on The Suite Life On Deck.
 * Nickelodeon as well:
 * ICarly: Carly/Sam/Freddie A plot, Spencer (and later Gibby) B-Plot. Formula for dozens of episodes. Occasionally one of the trio jumps into Spencer's plot whilst the other two deal with the A-plot.
 * Victorious: Tori in the A-Plot, and a B-Plot which uses cast not required for the A-Plot. Trina is often what the b-plot revolves around.
 * Then the two shows had a crossover special, leading to an epic 10 Lines, No Waiting: Carly's time with Steven, Tori's time with Steven(which later intertwine), Andre and later Kenan trying to catch the panda, Robbie/Rex in an epic rap battle, Cat having to use a headband to talk, Trina babysitting for Lane, Sikowitz trying to scare Beck, Spencer, Beck, Jade and Sikowitz in the hot tub, Sinjin video game surfing, and Gibby trying to find his mole. Eventually all the plots build into one another leading to everyone singing karaoke.
 * Drake and Josh: The titular brothers in the A-Plot, Megan in a B-Plot when not directly involved in screwing up the A-Plot for the boys.
 * Zoey 101: Same thing as Victorious except Zoey in place of Tori.
 * Ned's Declassified School Survival Guide: A-plot with the main character that may involve one of his friends, and a B-plot that involves the other friend.
 * HBO's Oz featured several continuing plotlines in more of a serial format (starting and ending with the season), as well as single-episode plots.
 * Often seen in the British mystery series Rumpole of the Bailey. A typical Rumpole episode involves two plots: the case of the week Rumpole is defending, and a plot involving either some intrigue back in chambers or some intrigue in Rumpole's household.
 * Soap Operas... all of them. The general practice to have three main plots running: one in infancy, one at peak and one wrapping up.
 * Over in non-fiction land, Myth Busters does this too.
 * Partially justified in that a single myth is generally too short to provide a thirty minute show. However, it is the presentation of each myth in parts that qualifies Myth Busters as an example.
 * In documentary TV, each The First 48 episode tracks two murder investigations, each in a different city and having nothing to do with each other.
 * Intervention follows two families coping with addictions, cutting back and forth.
 * In its first season, Heroes did a very interesting bit with this in the long-arc scenario. It has multiple long arcs -- Nikki/Ikkin, Petrelli Bros., The Bennets, Hiro's Quest, and Sylar (roughly) -- with an encapsulating long-arc. Each sub-arc gets some screen time every episode, with the emphasis (length) shifting from arc to arc. Fascinating bit of juggling.
 * Less obvious is the title names for each episode. They're metaphoric and (usually) can apply to any and all events that occur in a single episode.
 * Later seasons tried similar juggling, but balls got dropped, and things sprang out of nowhere and didn't always connect to the other threads, and it generally exemplified how to not do this. The last season got back on track (though not quite as adept - there wasn't room for everything to prove terribly important, and characters went absent longer than they would in S1, but it was a marked improvement.) but not in time to save the show.
 * My So-Called Life usually had a B story involving Angela's parents, thanks to child labor laws (Clare Danes and Devon Gummersall couldn't be in every scene of the show.)
 * Exception: Everybody Loves Raymond is unique in the sense that every episode followed one storyline, there were no subplots. Yet it was still very successful and ran for nine seasons.
 * Not necessarily subplots, but they did have minor inter-episode stories as running gags, such as periodically reverting to the arguments between Marie and Frank (over things like what constitutes something as 'fork-split,' who will die first and what the remaining one will do, etc) throughout the episode.
 * Seinfeld perfected this tactic, with a twist. The two story lines would turn out to be physically (not just thematically) interrelated through some absurd coincidence or twist. Larry David has mentioned in several DVD commentaries that he had the idea to interweave the separate plotlines early on in the show's run, but didn't perfect the practice until Season 4.
 * Lost does a variant on this pretty much every episode: one Backstory-revealing plot told in a series of FlashBacks, usually thematically related to the primary "present day" plot.
 * And now in the fifth season, the flashbacks are gone and instead the episodes are split between the group of people on the island and the Oceanic Six.
 * The second half went back to the flashback format, but abandoned the "two present day stories" for, at-episode 10, 12, and 13 were centered on only a single plotline, 11 only featured a brief scene from another, and 14's b plot was only a few scenes at the start and end.
 * In a number of episodes, there's not only the Flash Back and the "present day" plot but also a secondary "present day" plot that's more lighthearted and features the leftover characters. There have been cases of people playing golf and table tennis, and Hurley & Sawyer tracking then squashing a noisy frog (seriously).
 * Most of season six has three plot-lines per episode: two of the Island groups are featured, along with a story set in an alternate universe where 815 never crashed.
 * Northern Exposure typically had three or four plotlines per episode.
 * The Bill often does this.
 * Scrubs does this often, and tries to tie them together in a central theme at the end. This has become embarrassingly annoying and contrived in later episodes, where it is clear the writers are merely writing this way because they have set up a style they feel they cannot deviate from, and have run out of clever ways to tie the different storylines to a central theme: "It's hard living life... whether it's giving birth on a sinking submarine... eating a fellow doctor's testicles... or just plain sitting around at home in your jammies, smearing baked beans on the TV."
 * In My Waste of Time, J.D. lampshaded this practice by saying his moral out loud in front of others after having an epiphany:

J.D.: Oh, I'm just doing this thing where I use a slice of wisdom from someone else's life to solve a problem in my own life.

Jordan: Seems coincidental.

J.D.: And yet I do it almost every week."

"Hank: Maybe The Littlest Hobo was the first ever reality show, did you ever think of that?
 * In some commentaries and interviews on Scrubs DVD sets, it is mentioned that Bill Lawrence's parents found it hard to keep up with the multiple storylines. Sucks to be old, I guess.
 * This really hurt some of the more dramatic episodes near the middle of the series' run. "My Lunch" is a commonly lauded episode with a high drama factor. The A plot deals with organ transplants to several patients, almost all of whom won't survive without immediate surgery. The B plot consists of Carla and Elliot trying to convince Todd that he should admit to being gay, leading to him harassing both male and female characters from that point on.
 * Seacht seems to be doing this with Decko, whose interaction with the rest of the cast has so far been minimal.
 * Dawson's Creek always had more than one storyline but for much of the post High School 5th and 6th seasons (especially the latter), interaction between the storylines was minimal, or non-existent.
 * Friends did this quite often, usually preferring the three-storyline model. The relationships between the characters allowed some fluidity in the pairings.
 * "The One Where They're Going to Party" - Ross, Chandler, and Joey in Plot A, Monica and Rachel in Plot B, and Phoebe in Plot C.
 * "The One Where Ross and Rachel... You Know" - Ross and Rachel in Plot A, Monica and Phoebe in Plot B, and Chandler and Joey in Plot C.
 * Particularly in later seasons, episodes frequently split along with the Ships: Ross and Rachel, Chandler and Monica, Phoebe and an outside cast member (Duncan, Eric, Mike, and so forth.)
 * Duncan was actually a love interest for Phoebe in the second season, before all the major couples paired off.
 * Two-story episodes were still common, though: "The One with the Routine" had Monica, Ross, Joey, and guest character Janine in Plot A, with Chandler, Phoebe, and Rachel in Plot B; "The One with the Blackout" had Chandler by himself in Story B, while everybody else was in Story A.
 * How I Met Your Mother works this trope similarly to Friends. The A Story usually runs through Ted, while the B Story tends to involve the stable couple of Marshall and Lily. Barney and Robin sometimes end up in their own plotlines, but are more often part of the A Story or B Story.
 * Season 5 places the main focus away from Ted more often than not; Barney and Robin's romantic subplot takes up most of the first half of the season, Robin and Don take up the second half, with Marshall and Lily's attempts at having a baby the standard B-plot. Ted himself rarely stars.
 * The delicate balancing of sitcom hijinks and medical/war drama seen throughout M* A* S* H appeared to be a little too much for the writers to handle in the last few seasons, so instead every episode was given two storylines, one funny and one serious. It was rather obvious that they were putting all their effort into the serious storylines and the "funny" storylines tended to fall flat as a result.
 * Corner Gas has two or three storylines per episode, which is merely one of the reasons it's often compared to Seinfeld. Its larger main cast (more than four) divides up pretty evenly among the storylines. This is most interesting when the divvying of the storylines doesn't happen according to the common pattern (the two police officers, the old married couple, the gas station workers--Hank functions as a wildcard, who may have his own storyline like a Good Hair Day).
 * The Littlest Yarbo where Hank discusses his plot, and Brent randomly starts talking about his own:

Brent: Hold on here! If I can see my logo, then her logo is on the outside all the while giving her free advertising!

Wanda: Come on, guys! I can only handle one weird obsession at a time!"


 * This became increasingly common in later seasons of Married... with Children, with some members of the cast getting involved in their own side adventures away from the main plot.
 * The Canadian drama series Da Vincis Inquest was cancelled in part because of this trope. At the end of the series, the main character, a coroner living in Vancouver, successfully announces his bid to become the Mayor of the city. In the spin-off/sequel, Da Vinci's City Hall, the story balances the problems he has while in office, his quest to get a "red light district" up and running, his bid to create safe-injection sites for drug users, the trials and tribulations of his former partner working at the city morgue, events happening at a police station...if you missed one episode, you were lost. The show suffered in the ratings, and was cancelled as a result (although there may have been other motives).
 * A rare case of a show being submarined by its own Truth in Television: the Da Vinci character was based on real-life Vancouver mayor Larry Campbell.
 * In Super Sentai and Power Rangers, most episodes revolve around two plots: A Monster of the Week and some real-life challenge for one or more of the main characters. In many cases, the two get interwoven, with the everyday plot ending up teaching one of the Rangers a valuable lesson which then becomes instrumental in defeating the Monster of the Week.
 * One particularly memorable Law and Order episode actually screwed with the long established premise of one case, one episode, by showing a day in the life of the police officers and their relations with the D As. Rather than the one case followed from crime to verdict, one principal case is brought up, and several other minor cases crop up to plague the detective's concentration. Like all episodes, however, the detectives are able to solve all the cases by the end of the day.
 * Used on Frasier many a time, with one episode ("Death and the Dog", Season 4) hanging a lampshade on it. The events of the episode are being told as a Whole-Episode Flashback to a caller, and Roz wonders why Frasier is telling the caller about her date in the episode.
 * The Shield usually runs three police plots (the Strike Team, Dutch and Wimms, Danni and Julien), plus Macky's private and Aceveda's political lives, with plotlines crossing and merging.
 * Malcolm in the Middle did this every episode, typically with three storylines running at once or more. The most common one was the A Story being about Malcolm and one other family member, and the other stories revolving around the other family members and Francis always had his own story.
 * Grey's Anatomy does this in a way similar to Scrubs but usually a lot less contrived and there is almost always a real struggle with morality that Meredith references when she does the voice over in the beginning and end of an episode. If the plots are too separated, the writers link it together with a more broad aesop... like "trust your closest friends" or something. Clever!
 * To be fair, Grey's hasn't been on the air as long as Scrubs. The plot device didn't feel all that contrived on Scrubs in the earlier seasons. Scrubs even pointed out when Grey's started losing the edge too and going for the broader aesops with a little bit of a Take That.
 * The West Wing does this a lot, and also frequently juggles three or more storylines per episode.
 * Happened quite a lot in Boston Legal, as different characters are taking different cases, usually with one case being the serious one with a Character Filibuster or Author Filibuster in it, and the other case being the slightly light-hearted one (usually involved Denny Crane)
 * Pushing Daisies usually only has one actual murder mystery per episode, but there are other personal plots for the characters to deal with at the same time. In some of the later episodes, two of the main characters would investigate the case while the others had something else to do.
 * True Blood is setup like this. The main story is usually focused on Sookie and Bill. Sam and Tara have their own subplots which cross with each other and Sookies from time to time. Lafayette and Andy show up regularly with their own problems, but not as much time is dedicated to them. Meanwhile Jason is off doing his own thing.
 * Most episodes in the new series Lie to Me involve two different investigations going on at the same time. In a standard episode Cal and Ria will be investigating a death or a murder while Gillian and Eli are investigating a scandal.
 * Every episode of season one of Naturally Sadie would have one 'Sadie' plot and one 'Rain' plot, except one where the plots merged. This was less common for the second and third season.
 * This became the standard for Blakes Seven. With several main characters the writers needed to find something for all of them to do, and so the plot would often split up into two lines: the first for the ones who make planetfall Down There, and the other for the ones who run into trouble Up There on the Liberator (and later on Scorpio).
 * Most episodes of The Closer have the investigation as the A plot and something involving Johnson's personal life as the B plot. Usually they're tied together thematically and/or the B plot provides the weekly Eureka Moment. In addition, the B plots often stretch for more than one episode.
 * Desperate Housewives usually has 5 plots running simultaneously; one for each of the four main housewives and one involving the season's Big Bad or creepy/mysterious neighbor. These plotlines will mesh in the big catastrophe episodes, but generally stay apart.
 * Used in nearly every episode of The Mentalist. Plot A follows Jane with the murder mystery and whoever happens to be his sidekick this week, usually Lisbon or Cho. Plot B follows the more exciting cop business with Rigsby and his sidekick of the week. Sometimes the plots are related, and sometimes they're not.
 * Warehouse 13 has seemingly switched to this in Season 3. With the addition of Jinks, the pattern (so far) is that Pete and Myka search for artifact A, Claudia and Jinks search for artifact B.
 * It's Always Sunny in Philadelphia usually begins with the gang getting to an argument and then splitting off into two groups with different objectives as the result of the argument, which form the two plots of the episode.
 * Castle has this as well. The A Story centers around the crime drama, and the B Story centers around Richard Castle's family drama.
 * In Boy Meets World, most episodes had an A plotline with Cory, Shawn and Topanga and a B plotline with Eric (and Jack starting in season 5 and Rachel starting in season 6), though this varied a good bit. In many of the later season episodes one plotline was serious while one was comedic.
 * Very common in Chuck - the A story revolved around Chuck, Sarah and Casey, while the B story revolved around Chuck's friends at Buy More.
 * Burn Notice does this in practically every single episode. One storyline will involve tracking down the people who burned Michael or, in season 5 . This will invariably bring Michael one step closer, but won't result in a major development unless the episode is a season finale. The other will be generally involve saving an innocent victim form the Monster of the Week. Seriously, this formula is used so consistently, one has to wonder how none of the characters ever seem to notice that its happening.
 * Kamen Rider OOO, a season of Kamen Rider with Rule of Three as its central premise, would often advertise its unique concept of Three Lines No Waiting across every two episodes, complete with a "Previously On..." segment recounting "these three things" - as the series went on, they would often seperate a plotline's cause and effect to make up the number.
 * The Big Bang Theory: After Amy and Bernadette joined the cast there were several episodes that featured one storyline for the men and one for the women with little if any overlap.
 * Jeeves and Wooster would quite often have two separate plotlines that Bertie Wooster got involved in. This was due the screenwriter, Clive Exton, often combining two different short stories into one episode.

Music

 * Spoiler Alert by They Might Be Giants tells two stories, one of Flansburgh, a truck driver who believes his truck can drive itself, and one of Linnell, who is distracted with writing a story and thinks he has more hands than he does. Presumably, they collide at the end.

Theater

 * Shakespeare's Much Ado About Nothing has two love plots -- Claudio and Hero, and Beatrice and Benedick. A Midsummer Night's Dream has the "lovers from Athens" and the Oberon-Titania plots. King Lear has the plot about the King, and the plot about the Duke and his two sons.

Video Games

 * Halo 2 did this with the Master Chief and the Arbiter. The Broken Base is still debating if it was a good idea or not.
 * Some of the Final Fantasy games, most notably Final Fantasy VI and Final Fantasy IX, make use of this trope. At one point in Final Fantasy VI, the characters splits up into three groups, and the player plays through each of their stories in turn, before they all reunite in Narshe. In Final Fantasy IX, the party members split up halfway through Disk 1 to comply with the game's Arbitrary Headcount Limit, and the story shifts back and forth between them until they reunite halfway through Disk 2. Final Fantasy XIII does this for most of the game- it's only 25 hours in where you finally get all six party members together.
 * The mission system from the Grand Theft Auto series is a version of this. The missions come in multiple chains, with certain bottleneck events that bring threads together that must have all their prerequisites met. There's an internal mini-story to each line, but they are for the most part order-independent.
 * The first two Saints Row games did this as well, with the separate gang storylines being entirely independent. Which lead to characters involved in them only appearing in one of the three, as and the game has no way to determine in which order you've completed missions up until the final stretch. The Third changed this around a bit, where missions overall follow one plotline, and most times where you have a choice of two or more missions they're just one of your lieutenants asking you to play an activity.
 * King's Quest VII had the player alternate each chapter between playing as Valanice and playing as Rosella, each trying to find each other. This was the only King's Quest game with two playable characters (and oddly enough, the only one where King Graham makes no appearance).
 * Done twice, in Sonic Chronicles. First, Chapter 5 has Sonic, Knuckles, and two other characters make their way to Angel Island, while simultaneously Tails and head up another team trying to gather pieces to build a weapon. Chapter 10 has Sonic and Tails lead a team after one of Ix's dragons while Knuckles and  go after the other.
 * The Sonic Adventure Series does this in both games. The second having two (Three if you count Knuckles' subplot) interwining stories, the first having six (Seven if you count Tikal's subplot), that all come together in the end.
 * Fahrenheit (2005 video game) had two interwoven plotlines: one about Lucas trying to find explanation for what's happening to him and evade the police, and the other about Carla and Tyler trying to catch up with Lucas and understand what's going on.
 * Dreamfall was originally planned to have three full-weight storylines, one for each main character, however, only Zoe's actually counts as such. April's line is limited to two significant events, while Kian's consists effectively of a single dialogue and its consequences. Nevertheless, the lines are there.
 * Kingdom Hearts Birth By Sleep does this, with each of the three playable characters' stories happening at the same time, and meeting up on occasion.
 * Chain of Memories as well, with Sora and Riku running two unrelated plots that happen to take place in the same castle.
 * Dragon Quest IV had five chapters. Chapter 1 followed Ragnar, a knight trying to find missing children. Chapter 2 followed Alena, a Rebellious Princess who wanted to fight in a tournament, and her advisers Clift (the healer) and Brey (the wizard). Chapter 3 followed a merchant named Torneko who wants to start his own shop in the kingdom of Endor. Chapter 4 followed Manya and Minea, two magical sisters (a glass cannon and a healer) trying to avenge their father's death. Finally, chapter 5 followed you, the hero, and you get the entire party together, but you can only control yourself directly. In the new DS version, there's a sixth chapter where the Big Bad joins your party.
 * Suikoden III makes use of this trope through the Trinity Site System, allowing the player to tackle the story of three to different protagonists that happen roughly at the same time..
 * The newer Call of Duty games have this, with the game switching between the viewpoint of two main characters(and occasionally a third character for a single mission). In the Modern Warfare games, The American character is usually engaging in some big urban battle while the British character is doing some kind of special ops raid, more or less at the same time. Though In World at War, however, there is no connection between the two characters, one in Russia and one in the Pacific; the plot just switches between them every few missions presumably for a change of pace. Black Ops does this with Hudson and Mason's roles in the story and even once going through the same level from different starting points (Mason sneaking into the Soviet base to kill Steiner, Hudson and a group of American soldiers going into the facility another way to rescue Steiner. The two plots join up in the end, the final cutscene of both being the same scene from different points of view, which is also the final clue that Reznov )
 * Infinity series:
 * Ever 17 does this during the prologue of the game, switching between Takeshi and The Kid. It drops this shortly into the game, at which point the player is locked into one of the two characters.
 * Remember 11 has its prologue set up the same way, with Kokoro and Satoru being the viewpoint characters. While this game does force the player into one of the two characters after the prologue finishes, it continues to use this trope throughout its entirety during the personality transfer phenomena, resulting in part of each story being seen no matter which character the player is.
 * The fourth entry in the Front Mission series begins in the role of Elsa, a young Wanzer pilot in the employ of a multinational research team Durandal, sent to track an anonymous attack on several German bases. Not several missions later, you switch characters and play Darrill, a UCS soldier in Venezuela who deserted his unit with his two buddies to make off with loads of stolen gold. Both of these stories later evolve around a common theme of anonymous, state-backed hired mercenaries, and while the two don't directly intersect and interact explicitly only once, the two storylines gets wrapped up very nicely.
 * Winback 2 has you play each mission from the POV of two different operatives.
 * The first act of Syphon Filter 2 alternates control between Gabe and Lian at the same point in time.
 * Leisure Suit Larry 5.

Web Comics

 * In The Adventures of Dr. McNinja #6, #7, and #8, the doctor is searching for Dracula in the A Story while his sidekick and family train and fight a ghost wizard in the B Story..
 * Each chapter of Megatokyo (with the exception of Chapter 0) usually follows three plots, with the A Story focusing on Piro and Kimiko, the B Story focusing on Largo and Erika and the C Story featuring Miho, Yuki, Ping, or any combination thereof; although they nearly always intersect.
 * Questionable Content usually juggles several storylines, with new ones picking up and old ones ending fairly regularly, along with occasional one-off gags unrelated to any of them.
 * The basic MS Paint Adventures structure is to start with something very simplistic, then introducing more and more characters, each with their own different storylines and plots, and becoming incredibly convoluted and ridiculous, then slowly but surely dragging those plots together and suddenly, before the reader even knows it, it's all one story.
 * Captain SNES has several storylines all running semi-simultaneously, which are hinted to tie together in the end. Between the length spent on any given storyline and the Schedule Slip problems, threads can be dropped and picked up again quite literally years later.
 * Rumors of War begins its first Story Arc with the cast assembling, then follows two characters as they go about separate, unrelated activities. The first is an information-gathering trip that gets hijacked by a mystery and the other is a recruitment plot in the style of a Short Con.
 * Bob and George habitually cut between storylines.
 * Irregular Webcomic is entirely made up of B storylines! There's no main plot, except for crossover between plots, so at any given moment there's seventeen different stories going on simultaneously (plus the Miscellaneous theme, which doesn't have a coherent plot or characters), although of late the primary ones are Steve & Terry, Fantasy, Space, and Cliffhangers, with secondary (but still important!) ones being Myth Busters and Scientific Revolution. And something's happening with the Shakespeare theme, and I guess the Nigerian Finance Minister and Pirates are still out there somewhere... Anyway, with so many themes, there are frequent crossovers; at one time, fourteen of the different themes converged for the destruction of the universe! (not included were Miscellaneous, which doesn't have a storyline; Supers and Espionage, which exist in a totally separate continuity (OK, so there were a couple of Espionage crossovers, but for the most part it's separate!); and Scientific Revolution, which is a relatively new theme.)
 * Used in Our Little Adventure. Julie and her group's adventures to collect the Magicant and solve their world's problems is the A Plot. Zaedalkaah/Umbria's release, meeting with Trevoricus and Jason and joining with Angelo's kids as part of her quest to get her body back is the B Plot.
 * In American Barbarian, Two Tank Omen's advance and Yoosamon's talking with the king parallel in every strip for a while.
 * Tides Of Change switches between Tides of Change set in the past and The Dragon Rider, set several thousand years later in the present. Only recently in the story have connections beween the two started appearing in the stories.

Web Original

 * Survival of the Fittest. One for every. Last. Character. Of course, there are intersections, but essentially every character has their own story. Some of the time, these stories are part of another character's story.

Western Animation
"Lisa: I feel so terrible. I just wanted to save those animals while Bart became a drummer, but I never thought the two stories would intersect."
 * Done a lot on The Simpsons, usually with one story about the adults and one story about the children, although later episodes seem to have become exclusively one story affairs.
 * Still associated enough with the show to occasion a Lampshade Hanging here and there. In "Jazzy and the Pussycats", Lisa is envious of Bart's newfound success as a jazz musician, and also adopts a pet tiger that maims him.

"'Captain Hero': Hey subplot, outta my way. Main story comin' through!"
 * Lampshaded in the episode with Bart's vision of the future: "Why is there a story about Homer and Lincoln's gold in my vision?" "I guess the spirits thought the main vision was a little thin."
 * Newer episodes are more fond of a version of Halfway Plot Switch -- a plot hook is set up in the first five minutes, and then promptly dropped when something even wackier comes along. Sometimes invoked in the same episode as Two Lines, No Waiting, giving an A plot, a B plot, and an "aborted" plot.
 * Avatar: The Last Airbender regularly utilizes Aang and the Gang for "A" story, and Zuko and Iroh as the "B" story, to emphasize the similarities and flaws between the main protagonist and the main antagonist. Though Zuko served as a source of conflict for the heroes initially, his own separate stories became much more frequent and gained much more depth after his character was developed, eventually earning him A Day in the Limelight in the second season to delve in his backstory by means of a Whole-Episode Flashback.
 * With that and his Heel Face Turn in mind, one can realize that from "The Firebending Masters" to the Grand Finale, Zuko shares plots with the Gaang.
 * It is even Lampshaded by Toph when she said she was the only one who didn't have a "life-changing zuko field trip",
 * Almost every Drawn Together episode had two different stories ongoing, usually not intersecting with each other, with different subsets of the main cast. Like just about everything else in the show, this has been Lampshaded a couple of times, once by Toot who, following a battle with a live action cow, was thankful that she "was in the other story", and again by Captain Hero, whom the show had begun focusing on in the second season onwards:


 * Kappa Mikey is fond of this, to the point where episodes where it doesn't happen are the exception. Generally, the point of this seems to be making sure everyone's in the episode, though the extent to which anything can be rationalized on that show is debatable.
 * Some Danny Phantom episodes focus on main character Danny handling his own affairs while the B plot takes a look at the ongoing of his best friends Tucker and Sam. The two plots usually join up as one by the end.
 * Many Danny Phantom episodes also have two separate plots covering what goes on in high school, and what goes on with the ghosts. One good example would be "Parental Bonding"--high school dance coming up, and a ghost amulet that turns the wearer into a dragon.
 * South Park used to do this every episode (or close to it). It still happens on occasion. Usually one plot influences or causes the other in some way but they aren't necessarily tied back together (for example, in "Krazy Kripples," Timmy and Jimmy joining the crips is directly caused by Christopher Reeves' appearance in South Park, but they never end up meeting him)
 * In the commentary, the creators said that they originally felt they had to do two or three stories every episode and found this very tiring. They eventually started doing only single-story episodes, and found these to be much funnier and generally better episodes. They try to keep it simple these days, though they do handle multiple story lines on occasion.
 * Transformers Animated did this in one episode. Story A had Optimus Prime and Sentinel Prime's head facing off against the Headmaster armed with the rest of Sentinel. Story B was Sari angsting over her non-(legal) existence with Bumblebee and Bulkhead trying to comfort her.
 * American Dad is constantly using this usually by introducing a side plot loosely connected to the main plot at the beginning but letting it go it's own way instantly. Sometimes they intersect again at the end but not always. Klaus lampshaded it when he was The Narrator for his grandson and introduced the Steve subplot while the focus was on Stan and Francine ice skating.
 * Not to mention that Finances with Wolves is an episode with Five Lines No Waiting, with Francine, Roger, Klaus, Hayley, and Steve each get plots with equal merit.
 * Family Guy used to do this sometimes in its first three seasons; became less frequent post-cancellation. Many episodes focus on just one plot, but a couple of them ("Stuck Together; Drawn Apart" comes to mind) had a pair of unrelated main plots going at the same time.
 * Almost every episode of Phineas and Ferb features an "A" plot about the title characters (usually building something amazing), and a "B" plot in which their pet platypus Perry works as a secret agent against the local Mad Scientist Dr. Doofenshmirtz. The "B" plot usually ends up physically affecting the "A" plot (for example, Doofenshmirtz's machine somehow destroys the boys' invention before their mom discovers it), but the plots are (usually) thematically unrelated. Phineas and Ferb never become aware of the "B" plot, at least not enough to discover Perry's secret.
 * One of the only episodes to break this pattern, "Phineas and Ferb Get Busted," focused only on the boys and their sister's plotline until Perry and Doofenshmirtz are needed, at which point they suddenly appear fighting on top of a mechanical spider. Which is made weirder when, calling into question why that was the plot to get so much focus.
 * The Venture Brothers does this often with two stories going on at once that come together near the end. This is due to Doc Hammer and Jackson Publick often writing separate stories and slamming them together near the end. "Escape to the House of Mummies Part II" plays the disjointedness of the two lines for laughs. The episode starts off all the main characters having a mummy-themed adventure together. Dr. Venture escapes back to his house and promises to return and save everyone, but he almost gets sidetracked by an unrelated side-plot instead. This becomes the A plot, and the show occasional jumps back to the other characters to show them dealing with the much more exciting B plot.