Mandatory Line

""I have one job on this ship--it's stupid, but I'm gonna do it, OK?""

- Gwen DeMarco, Galaxy Quest

When a character has a scene or bit of dialogue which is unnecessary and oddly out of place, it may be because the writers couldn't work them into the plot of the episode and have just given them a few token lines because the actor's contract requires it. Sometimes a character will get two or three moments like this in a single episode, to give the illusion that they're properly involved in the plot when they're really not.

This trope can be seen in ensemble shows where most of the characters are together (say, a starship bridge crew), but several (the doctor, the engineer) are not, and have no real role in the story.

(EX: Starship Enterprise, in the middle of a firefight) "Picard: "Mr. LaForge, status report!"

Geordi: "The power grid is down 20%, and I have no more lines.""

Alternatively, if we're having a Lower Deck Episode, or a Mauve Shirt is getting a Day in The Limelight, the rest of the regular cast will get the Mandatory Line instead - either one by one through the episode, or providing some sort of framing device or fluff B plot.

With the growing trend of shows with Loads and Loads of Characters (such as Heroes and Lost) this is becoming less common, and it is typical for characters to be completely missing from episodes. Some shows, such as Law & Order: SVU will alternate pairs of detectives so that two episodes can be produced at one time. Frequently occurs with Poorly Disguised Pilots, where the main characters will have just enough screen time with the new characters to justifiably call it an episode of the parent show, then will dive headfirst into the spinoff characters, often never even referencing the main characters again.

Anime and Manga
"Daichi/Bastion: Well, it is... sort of romantic..."
 * Happened once with Daichi/Bastion Misawa in Season 1 of Yu-Gi-Oh! GX and may have been a early sign of what was to come. Over the course of two episodes, he only had ONE LINE:


 * Hayate the Combat Butler OAV, both Klaus and Tama (not a line in Tama's case) get these, which are then lampshaded by the narrator stating 'end of screentime'.
 * In the Trigun episode "Little Arcadia," the main protagonist, Vash, appears in both major fight scenes for all of about a minute total of episode time. However,.
 * Vash: "That makes us even for helping me on the sandsteamer. Huh? Wait, is that all the time I get?"

Film

 * The entire concept was viciously parodied in the movie Galaxy Quest, where the one female character's only purpose on the show was to repeat word for word anyone else's questions to the computer and the computer's (audible to everyone) replies. When someone questions her doing it, she angrily snaps that it's her one job and she will not give it up. As the scene goes on, it seems that the computer will only respond to her anyway.
 * Ginny Weasley in The Film of the Book versions of Harry Potter and the Prisoner of Azkaban, Goblet of Fire and Order of the Phoenix. In Azkaban, she literally had one line. At least she still appears...
 * Draco Malfoy had only two lines in the fifth movie. His big role in the next movie made up for it, though.
 * Neville always gets to say something in every movie, regardless of whether anything else with him happens.  Doesn't mean his role is unimportant.
 * Averted with Wormtail, who appears in the sixth film, but doesn't have any lines in it. And Timothy Spall still gets credited as part of the main cast!
 * Arwen does not appear in The Two Towers book, yet she graces the film in series of dream sequences and flashbacks.

Live-Action TV

 * Obviously, Star Trek used this trope abundantly, but special credits go to Harry Kim of Voyager and Travis Mayweather of Enterprise, as most of their careers seem to be made of this.
 * Even the starring roles can get this from time to time. Captain Picard only gets one line in the very final scene of the Next Generation episode Thine Own Self, and there are a few episodes of Deep Space Nine where Captain Sisko only gets a line or two as well.
 * At the beginning of season three of Buffy the Vampire Slayer, Angel (who was supposedly lost forever in a hell realm) appeared only in a series of dream sequences.
 * Angel fell victim to this in the previous season, too. After he became the season's Big Bad, it made sense for him to show up in the arc-relevant episodes, but they had to find excuses for him to appear in standalone eps where he wasn't actually causing any trouble, too. So there were several instances where he would randomly bump into Buffy in an alley someplace, say something mean to her, and then leave, adding nothing to the plot.
 * Perhaps the worse example was in "Phases"--the episode was Oz-centric, and about werewolves, of all things. Angel did nothing but pop up with a new coat of badass guyliner, turn some random girl into a vampire, and stir up a bunch of old tensions between Buffy and Xander.
 * Similarly, Spike, throughout season four, now had a place in the credits, so it seemed every episode from then on needed to have a scene randomly inserted where he showed up, complained about his ongoing emasculating Badass Decay and left.
 * In the BTVS Musical Number "Once More, with Feeling", Willow only sings one line in the big all-cast number at the end: "I think this line's mostly filler". While she does have a few singing lines throughout the episode, they are very few and far between - "her" song is sung entirely to her by Tara.
 * That's because Alyson Hannigan is song-shy and she asked Joss Whedon to leave her out of the singing as much as possible.
 * Which might be why her character on How I Met Your Mother is the only one of the main cast who hasn't yet had at least one number to sing.
 * This about sums up Cordelia's role in the bulk of Season One.
 * It is also why Seth Green left the series--he was tired of Oz just having his mandatory line appearances in most episodes.
 * On Angel, after Wesley became estranged from the rest of the group, several episodes had him appearing only to have a bunch of sex with Lilah and not do anything relevant to the plot.
 * Which is a pretty good consolation prize.
 * Occasionally done with the FDNY characters in the later seasons of Third Watch, which by this time was mainly focused on the NYPD characters.
 * Some episodes of Frasier struggle to include series regular Roz, whose only connection to the other characters is that she works for Frasier. In the later seasons she becomes close to the family and more involved in the A-plots.
 * In fairness, she does also frequent the same coffee shop (Cafe Nervosa) that Niles and Fraiser spend a remarkable amount of time in.
 * A better example from this show would be Bulldog, who was originally intended as a series regular, but almost immediately began appearing in cameo roles because his only connection to anyone was that he had the timeslot after Roz and Frasier's show.
 * Lampshaded in Monty Python's Flying Circus:
 * Terry Gilliam only makes one appearance in Episode 4, as a Horny Vikings who says, "This is my only line."
 * Episodes 4 and 8 both have a sketch where Michael Palin is an art critic and Katya Wyeth comes on and makes an Incredibly Lame Pun. When he complains about it, she wails, "But it's my only line!"
 * As noted above, Heroes generally averts this...except in season three, which has been criticized for (among many, many other things) shoving every major character into every episode whether they had something to do or not. While the show stopped this towards the end of volume four, for most of the run we had a surprising amount of scenes of people driving to a destination where something important would happen in a later episode that contributed nothing except getting everyone in briefly. Luckily averted in season four, where only about half the cast is in each episode.
 * Vanessa on Gossip Girl in about half of the episodes she appears in.
 * Nate and Jenny too, though to a lesser extent. There problem was they usually had a major storyline in the first half of the season and then spend the next 9 episodes on the back burner. This was especially egregious with Jenny in season 2 where she did nothing but sit around and play boardgames.
 * Rufus once he married Lily, since this all about ended his major storyline. Now he usually has one scene an episode where he gives Dan advice or something.
 * Frank Lapidus on Lost in the sixth season. His only function in the plot is to . He doesn't get any character development, isn't in the flash-sideways, and the only big arc about him (him being a candidate) turned out to not involve him at all. But he had to be included in the rest of the season, so all that was left for him to do was to pop in, give a cheesy one liner and then either vanish or stand around doing nothing for the rest of the episode.
 * To be fair, Lost's setting doesn't allow him to wander off and come back when needed, especially with him being very unfamiliar with the island.
 * Babylon 5, in general, averted this trope. However this aversion is actually responsible for Talia's actor leaving the show, as she is the person who would have gotten 'mandantory lines'.
 * Wilson on House has this from time to time. There are many episodes where he has a single scene with House (or one of the rest of the cast) that is, ultimately, pretty pointless and only serves to put him in the episode. The most blatent example of this is in the Season 6 premier, in which he is the only regular cast member to appear (other than House himself) and his appearance consists of a single, 30 second, completely plot-irrelevant phone call.
 * NCIS: On a few unusual episodes (hostage situations, etc.) they have to shoehorn Ducky in, though he usually gets an entire scene. They fail at this only once (Legend, part 2).
 * In season 2 of Merlin the writers suddenly seemed allergic to the possibilty of Morgana and Gwen (who were best friends in season 1) sharing any sort of dialogue with each other. With one notable exception ("Lancelot and Guinevere") the episodes will either focus on one female character or the other, requiring the superfluous one to voice her Mandatory Line before fading into the background.
 * Tina's entire role on Glee, where she is basically an Advertised Extra.
 * Kurt in season 2. He was separated from the main cast and at a boarding school yet the show still managed to crowbar him in, having a character come visit him or him go back home briefly just so he could have a conversation with someone.

Video Games

 * A common complaint about Golden Sun Dark Dawn was that whenever something happened, there would be a lot of extraneous dialogue boarding on Department of Redundancy Department as each of your party members commented on it. This was actually an attempt to fix a certain problem from Golden Sun: The Lost Age, but they went a little overboard with it.

Web Original
"Tea: I'm just here to look pretty!"
 * Lampshaded in Yu-Gi-Oh! The Other Abridged Movie:


 * Two terrific examples from That Guy With The Glasses, in their two Massive Multiplayer Crossover events. In the first one, the Epic Brawl, everyone was reduced to this except for the Nostalgia Critic and The Angry Video Game Nerd. The second one, Kickassia, was a little better about fleshing out the characters, but over half of the contributors (including fairly popular ones like Angry Joe and Benzaie) were still stuck in this mode.
 * "This is a sad day for Handsome Tom..."
 * Parodied with Sweet Cuppin' Cakes. No matter what the plot of the episode is about, sooner or later Eh! Steve! has to show up to deliver his catchphrase ("Eh! Steve!"), even if he's otherwise incidental to the plot.

Western Animation

 * Lampshaded in Duckman episode "Sperms of Endearment". After it was discovered that Bernice may be pregnant with Duckman's baby (due to getting a donation of his sperm), Cornfed suddenly appears at the door. Duckman says it's a bad time, but Cornfed states that his contract requires him to appear for at least 10 seconds in every episode.
 * In Captain Planet and the Planeteers, LeVar Burton's character, Kwame, delivers only one line in most later episodes. The same exact line. Actually a voice-only Stock Footage.
 * He apparently stopped showing up to recording sessions, so the writers never had his character speak, except for the previously-recorded intro line on the eponymous Super-Granola-Man's summoning sequence.
 * In Animaniacs, several episodes feature Wakko with very few lines compared to his two more talkative siblings. Most notably, in the Michelangelo episode, he only has two lines; one is only a single word. The Midsummer Night's Dream segment gives him only line: "Hello Pixie!"
 * In several later episodes of King of the Hill, Bobby, Luanne, and Boomhauer often had very little to do and either had one line of dialogue or never said anything. Given Boomhauer's role as The Unintelligible, nearly all his lines were bizarre or non sequitur.
 * Lampshaded in an episode of Family Guy. "If you want Cleveland to say his first line in the episode, text FAMGUY3!"
 * Lampshaded on American Dad in one episode which focuses solely on Steve and his friends. The rest of the family is not seen at all for half the episode, and when they do show up, they're all sitting together in the living room as Steve walks by and says one brief line to them. Stan says, "It sure was nice of Steve to acknowledge us this week, even if it was just this once." Other than that (and a quick, silent scene with Francine at the end) they don't appear for the rest of the episode.
 * Klaus has been pretty much reduced to this.
 * South Park episode "Red Man's Greed" featured one new character who was hanging out with the regulars, and who kept inserting random lines of dialogue that could easily have been cut without changing the main plot line at all. At the end, Stan and Kyle lampshade this by saying "Who the hell are you?" and telling him to get out, only for him to explain that he got to be in the episode due to a Real Life auction the network held. The boys tell him to go away. Rule of Funny, obviously.
 * The main Boys also make brief appearances in other characters' Days In the Limelight, usually with at least one scene or gag involving Cartman. It's worth noting that two of the least popular episodes are the only episodes to feature none of the main characters.
 * In the Daria episode "Jane's Addition," Daria's parents and Quinn do not appear onscreen at all. About three minutes before the end of the episode, they each say one word, bearing relevance to his or her seemingly simplistic personality. (eg, socially-active Quinn exclaimed, "Date!") Daria followed their lines up with a one-word quote of her own.
 * At the beginning of the third season of Drawn Together, Adam Carolla (who voices Spanky) had to miss two consecutive episodes due to scheduling conflicts. However, the producers made sure Spanky had dialogue in each episode by taking a couple of random lines recorded at other recording sessions and shoehorning them into the two episodes.
 * Lampshaded in "Captain Hero's Marriage Pact" when Toot and Clara show up out of nowhere at the end of the episode to comment on how they haven't been getting any screen time that week. This had nothing to do with ensuring that the actor got screen time, though, as Tara Strong, who voices both characters, would have been heavily featured in the episode anyway, as the voice of guest character Unusually Flexible Girl.
 * Terra appeared at the end of the Teen Titans episode "Winner Take All" just to prove she exists; she doesn't even talk though. It's especially noticeable because this was the middle of her arc. She joined the Titans the episode before, the next episode they don't try to mention why she isn't present, and the next episode.
 * Generally Ferb from Phineas and Ferb will speak no more than two to three times per episode. His lines are made all the funnier by how rare they are.