Castle (TV series)/Tropes Q to Z

"Alexis: Who's this new guy? It seems like he came out of nowhere.
 * Quip to Black: Castle, on a regular basis. Nobody else is amused. Beckett also gets to play sometimes.
 * Qurac: Played with in the second season finale. Beckett swallows the existence of a threat to the Banking Minister of the Republic of Luvania even though she had never heard of the country before, until Castle points out that it doesn't exist.
 * Race Against the Clock: As the title indicates this happens in "Countdown".
 * Reality Ensues: In "Always",
 * Real Life Relative: Seamus Dever (Ryan)'s wife Juliana has a recurring role as Jenny, Ryan's girlfriend.
 * The cast and crew have utilized it to very cute and very meta ends--such as creating a wedding website for Jenny and Ryan with the Devers' pictures.
 * Real Life Writes the Plot: In Seamus Dever's Episode Commentary for "Wrapped Up In Death", he says he broke his ankle three weeks before taping, encouraging the viewer to see how well he hides his limp. In the climax, the perp runs right past Ryan and Esposito, but instead of chasing after him, they just wave at him (the better to hide Dever's injury).
 * Really Gets Around: When Castle's mother says that he "never had a father figure", his reply is that he had dozens of them. Castle himself has a lot of female groupies. Lampshaded by Esposito in "Suicide Squeeze" when he jokingly comments on how active Martha probably was during the 1970s. Probably a mistake to say this directly to Castle, however, who is less-than-amused.
 * Recycled in Space: Jessica Fletcher Alternatively, Murder She Wrote meets Moonlighting and/or Remington Steele. Except that, unlike in Murder She Wrote, Castle isn't the killer. Or The Thin Man, only they're not married (yet) and she's the detective.
 * Red Herring: Lampshaded.
 * One of the biggest happens in "Pandora"/"Linchpin".
 * Redemption Equals Death:
 * Redemption in The Rain: Part of Beckett's epiphany in "Always" involves her brooding in the rain while sitting on a swingset. Word of God confirms that it's the same swingset she and Castle earlier had a meaningful discussion at in "Rise".
 * Remonstrating With a Gun: Castle in the season 3 premiere.
 * Retirony:
 * The Reveal: Castle's real name is finally dropped in "He's Dead, She's Dead". It's  which is incredibly amusing considering the daughter of a murdered psychic told Beckett that a man named   would be very important to her...
 * Revealing Coverup: The most common way Castle and Beckett figure out whodunit.
 * Ripped from the Headlines: The plot of "The Late Shaft" has a lot of similarities to the Jay Leno/Conan O Brien The Tonight Show controversy, as well as elements of David Letterman's recent affair scandal.
 * Romantic False Lead:
 * Two of them, each a date brought by Castle and Beckett to the same restaurant unawares. It lasts for all of 30 seconds before they're both making excuses to conspire about the case. Also a case of Pair the Spares because Beckett's date starts talking to Castle's date as Beckett and Castle leave the restaurant.
 * Detective Tom Demming appears to be shaping up to be one of these for Castle, regarding their mutual interest in Beckett.
 * As of "Overkill", . Alexis even does some Leaning On the Fourth Wall at the beginning of the episode, when Castle asks her to criticize a portion of his next Nikki Heat book, which, in case you've forgotten, is loosely based on what he does with Beckett.
 * As of "Overkill", . Alexis even does some Leaning On the Fourth Wall at the beginning of the episode, when Castle asks her to criticize a portion of his next Nikki Heat book, which, in case you've forgotten, is loosely based on what he does with Beckett.

Castle: He did, didn't he?"

"Ryan: Are we interrupting something?
 * In the third season, Gina and Josh take these roles for Castle and Beckett respectively, but were mostly The Faceless throughout the first half of the series. )
 * In "The Limey", Castle hooks up with a flight attendant some time after hearing . Colin, the British policeman, becomes this for Kate.
 * Room Full of Crazy
 * Rule of Funny: In "Heartbreak Hotel," Castle, Esposito, and Ryan get thrown out of an Atlantic City hotel because they're out of their jurisdiction. Do they call the Atlantic City PD for help? No, they sneak in by dressing up in Elvis costumes. And it's hilarious.
 * Running Gag:
 * Very frequently will someone catch Beckett and Castle in a highly UST-charged relationship moment or situation and / or will allude to them being in a relationship, prompting Beckett and Castle to respond unanimously -- with completely different responses (usually with Beckett hotly denying it and Castle cheerfully confirming it). Often something along these lines:

Beckett: No!

Castle: [At the same time] Yes!

[Beckett Death Glares Castle]

Ryan: ... Okay."

"Beckett: No.
 * In the first couple of seasons, whenever Castle mentioned who he was and his previous character, Derrick Storm (who was killed off in his most recent book before meeting Beckett), the person he's talking to would immediately enthuse "Derrick Storm? I love that guy! Why'd you kill him?"
 * Castle's Grammar Nazi tendencies and minor Berserk Button over people misusing Irony.
 * Castle and Beckett completing each other's sentences, usually leading to a breakthrough in the case.
 * The Sadistic Choice:
 * Safe Word: Castle's is 'apples', as he repeatedly mentions to Beckett.
 * Salt and Pepper: Ryan and Esposito. Beckett and Parrish.
 * Samus Is a Girl:
 * Saying Too Much: In the pilot the brother of one of the victims, when questioned for an alibi, helpfully provides alibis for all three of the murders. While Castle is downhearted, Beckett immediately pegs that while it's plausible he'd know his alibi for his sister's murder, the fact that he was instantly prepared for one for all three murders is more than a wee bit suspicious.
 * Scary Black Man: In Law and Murder
 * Scary Minority Suspect: Several. Usually Wrongly Accused.
 * Screams Like a Little Girl:
 * In "The Third Man",  Presumably a second occurrence happened just offscreen in that episode, as Castle was menaced by a big hairy spider.
 * Also he does a small one in "Tick, Tick, Tick...", when
 * Parodied in the outtakes when Stana opens a file and Nathan glances over at the picture before letting out a high-pitched, girly scream that startles the woman standing next to him and causes the rest of the set to crack up.
 * Screw the Rules, I Have Connections:
 * A non-villainous example would be Castle himself, who has the mayor on speed dial and can thus convince the NYPD to let him shadow Kate around indefinitely.
 * Captain Montgomery ultimately subverts this. He later reveals to Beckett that he could have gotten rid of Castle at any time ("The mayor doesn't run this place, I do"), but only kept him around because he thought it would be good for her.
 * Also subverted by the fact that the mayor is not merely doing Castle a favor, but is using his fame as a bestselling author to improve the police's reputation... as well as his chances to get reelected
 * Castle does the same thing when he learns that the fingerprints normally take a week to process and also to learn if a dead body is a CIA agent.
 * By the second season, the NYPD has basically said "screw the rules, you're actually incredibly helpful," and after resolving that rather uncomfortable tension with Beckett in "Deep In Death," the two are getting along fine, though they still exchange plenty of wit and snark. So now Castle just keeps helping with the cases, ostensibly still under the guise of novel research, but more because both he and the NYPD like having him around. As of S2 E5, 'When the Bough Breaks', he's on contract to write three more Nikki Heat books, meaning he's still fulfilling his original purpose.
 * In "The Third Man", Beckett does this to get into a high-end New York restaurant, surprising Castle, who didn't expect she had those kinds of connections. (He, of course, has plenty.)
 * In "Den of Thieves", Montgomery pulls a few strings to expedite a police report that could reveal a mole in a mob investigation from another precinct (which Esposito used to cover.)
 * Also, in "Kill the Messenger", Montgomery pulls more strings to smoke out a corrupted prison guard. Later subverted when a rich suspect threatens to call the police commissioner, Montgomery replies "Tell him I said hi. And that I could use a raise."
 * In "Setup", Castle offhandedly mentions that he's friends with the state governor in order to prevent Agent Fallon from kicking him off the case.
 * In "Rise", Castle uses this again on Captain Gates,
 * Though it could also be
 * Second Love: Beckett for Castle. His first real love was Kyra Blaine, introduced in "A Rose For Everafter." It's entirely possible there's some more out there, as we don't know who else he dedicated his books to (not to mention his two ex-wives).
 * He gets another before-Beckett love in Sophia Turner in "Pandora" and "Linchpin". Too bad she's never really left her First Love:
 * Secret Keeper: In season 4 "Cops and Robbers"
 * Self-Insert Fic: What Castle essentially turns his narration of the Blue Butterfly case into, as he visualises what the detective wrote, but overwrote relevant persons with himself and his friends. He even tries to get Ryan to say "Boyo" a few times (Ryan plays the role of an Irish thug in the narration), and flubs his narration and accidentally says Kate's name in place of Vera's (the detective's Love Interest).
 * Serial Killings Specific Target: In the pilot, the killer
 * Serious Business: In "A Deadly Affair" the entire precinct seems pissed off that Castle didn't call them at all during the Summer off -- Esposito said he should've
 * It's less that he didn't call them and more that he didn't call Beckett, who was hurt by it.
 * Sex With the Ex: Castle sleeps with his first ex-wife when she rolls into town for a short time. He compares it to a guilty pleasure. More seriously he re-kindles a romance with his second ex-wife when he thinks Beckett is serious with Demming.
 * Sharp Dressed Man: Castle has some really nice suits. Ryan also has a penchant for wearing three-piece suits to work.
 * She Cleans Up Nicely:
 * Beckett in "Home Is Where The Heart Stops" and in "When The Bough Breaks." Said literally to her, too.
 * And "The Third Man", of course.
 * "The Final Nail" club scene.
 * She Is Back: in "Rise", after having suffered a Heroic BSOD when, Beckett has to face the actual killer, who . She seems to be on the throes of a BSOD again, but Castle talks to her and she manages to pull through.
 * She Is Not My Girlfriend:
 * Brought to a head in "The Third Man" thanks to a newspaper article saying they're romantically involved.
 * "Kill the Messenger." Goes approximately like this:

Castle: [Simultaneously] Not yet.

Beckett: *glare*"


 * Comes up again in "Cops and Robbers," this time said word for word.
 * Sherlock Scan: Castle pulls this on Beckett in the pilot, as a sort of attempted Let's Get Dangerous moment to prove that he can actually help. It's played with in that Castle realizes as he's doing it that he's hurting Beckett and digging up painful memories for her, and apologetically stops without taking any satisfaction in being correct.
 * Shipping: Beckett gives a dictionary definition In Universe of this in "One Life to Lose" along with the Portmanteau Couple Name of "Fox Can." The first suspect was also suffering a bad case of Die for Our Ship for "Can Fonso."
 * In the same episode, Castle works out the Portmanteau Couple Name for Esposito and Lanie, "Esplanie". "Which is perfect, because they're always esplaining things!" Shippers for these two have used the term ever since.
 * Ship Tease: The entire point of the scene where Castle and Beckett kiss in "Knockdown". Well, that and
 * Find an episode that doesn't tease Castle and Beckett. Go ahead. We'll wait.
 * Possibly the most blatant Ship Tease so far was Ryan's wedding, where the show closes with Castle and Beckett walking down the aisle, hand in hand.
 * "Embarrassment Of Bitches" unexpectedly teases Esposito and Kay Capuccio.
 * Shipper On Deck: Lanie is the most obvious, but close behind her are Ryan, Esposito, Alexis, Martha, Montgomery...hell, it'd be easier to list who doesn't ship Castle and Beckett during the course of the show. Such as Gates. Notably, however, Kyra Blaine, Castle's first love, is also this. She pretty much explicitly gives Beckett her permission-slash-blessing!
 * And then, when beta (or gamma) offscreen couple is revealed, everyone else is fully in favor.
 * Shout Out:
 * A great many (some mentioned above) to several of the actors' previous works. See the Actor Allusion entry under Trivia for more details.

"Kyra: Out of all the murders at all the weddings in all the cities in the world, you walk into mine."
 * A couple to Alfred Hitchcock. The plot of "Double Down" is based on Hitchcock's Strangers on a Train, with both the film and the novel getting a mention. In "Tick, Tick, Tick," taxidermy is referred to as Norman Bates' favorite pastime.
 * "Little Girl Lost". Castle is asked why, with twenty-six bestsellers, he feels the need to shadow a cop. He points out that the ones on TV seem oddly fixated on their sunglasses.
 * When asked what they call perps, some of the names that the officers answer with are Skeksis and Sleestak.
 * In "Ghosts", they mention an old oil tanker bombing that crippled the captain. Who was the captain? Why, one Captain Pike.
 * In "Deep In Death", Beckett discusses how she sometimes visits Little Odessa (Brighton Beach, Brooklyn). When she was Hana Gitelman on Heroes, she tended to be in Odessa, Texas.
 * From the same episode, Castle grants Alexis permission to see Fame with her boyfriend "but I have dibs on A Christmas Carol." Alexis' actor, Molly Quinn, did voicework for the film.
 * In the season 2 premiere, Castle asks the coroner if she wants some music, because she's  and he says that in CSI they do it to music.
 * Anyone who follows Nathan Fillion on Twitter probably squealed with pleasure when in "The Double Down", he slipped in his catch phrase "Bam, said the lady", and again when he made the puntacular offshoot "Blam, said the lady" in "Last Call".
 * "Vampire Weekend" is full of Actor Allusions. Check that page for a list.
 * Castle references Underworld when talking about the body.
 * The episode itself is named after a popular indie rock band.
 * In "A Rose For Everafter," the name of Castle's New Old Flame is a Shout Out to Casablanca (Kyra Blaine), as are the resolution of the Love Quadrangle and this quote:

"Martha: "I am shocked, shocked, to find gambling going on in this establishment! [Pause] Deal me in.""
 * Quite a few to Casablanca, actually. In one episode, Castle is considering starting up his own bar, and trying to think up a name. His mother suggests "Rick's Cafe Americain". Castle says "That's much better than my idea: 'Castle-blanca'"
 * In "Den of Thieves", upon walking on Castle's poker lesson for Alexis, Castle's mom references Casablanca with a similar joke:

"Castle: Struck down by a killer with the speed and cunning of a bird of prey.
 * In "The Third Man" Esposito asks Castle and Beckett "why are you so obsessed with some motherfreaking snakes on a motherfreaking plane." Sound familiar?
 * Though probably not a shout-out per se, the baseball-themed episode "Suicide Squeeze" was written by Jose Molina...which happens to also be the name of a baseball player who most recently played for the New York Yankees.
 * In "Wrapped Up in Death", Castle finds a familiar looking brown fedora and whip, donning the fedora as he examines a sarcophagus. The episode title itself sounds like yet another murder mystery/bestseller reference, this time to the "In Death" series by J.D. Robb.
 * Three Scooby Doo references: Castle compared Beckett to Daphne and tells the villain "This is the part where you say 'And I would have gotten away with it too, if it weren't for You Meddling Kids!" and Beckett said the infamous "Ruh roh" towards the end of the episode after they find the killer.
 * You might notice a certain red hair talkshow host's Dwight Eisenhower mug in "The Late Shaft".
 * When Castle mentions a gun that shoots ice bullets, he's likely referring to a Dan Brown novel that involves this (at least in the first act).
 * Breaking Bad gets a shout-out in "A Deadly Affair," mentioned as "that cable show" about a high school chemistry teacher cooking meth, thought to be mirrored by the current case. The same episode gets a shoutout to The Man With the Golden Gun with Castle in the hall of mirrors in a pistol fight.
 * Castle gets to slip in a Double Rainbow reference while grilling Beckett over her lack of belief in psychics in "He's Dead, She's Dead".
 * It also makes references to the following famous time-travel works: The Time Machine, Back to The Future, and Time and Again.
 * Castle has a custom ringtone for calls from Beckett -- an Ominous Pipe Organ; he likes to say "I Hear Dead People" whenever it sounds.
 * "Anatomy of a Murder" has plenty of pretty blatant Shout Outs to Greys Anatomy. It's also the title of a court drama movie starring Jimmy Stewart.
 * In "Famous Last Words," the murder victim led a band called Blue Pill.
 * The same episode also contains a Jersey Shore reference where the names Sammy, Ronnie and Pauly are mentioned by a rather fake-tanned woman with a poof...
 * "Strange Encounters of the Murderous Kind" was one long The X-Files reference, complete with Castle as an Agent Mulder referring to Beckett as Agent Scully. Castle even whistles the theme tune at the crime scene.
 * Two suspects in "Countdown" are named Evan Bauer and Jack Cochran. In addition to the obvious reference, Robert Cochran and Evan Katz helped write, create, and produce the series.
 * In Pretty Dead, Beckett recalls that her beauty-pageant-contestant roommate made their apartment into their "own personal Vietnam." Castle responds with "I love the smell of hairspray in the morning. It smells like... victory."
 * "Heroes and Villains" is full of Shout Outs to comic-books including Spider Man, Iron Man, Daredevil, and Deadpool, as well as a Game of Thrones reference. And Shakespeare.
 * "Demons" has Castle pleading with Beckett to say it -- she "ain't afraid of no ghost".
 * In "Cops and Robbers" the robbers use the aliases Dr. Howser, Dr. Quinn, Dr. Huxtable, and Trapper John. There's also a mention of Die Hard, Dr. House, Dr. Shephard, and Dr. Phil.
 * In "The Blue Butterfly", besides the general Noir style, Castle makes an explicit reference at the end, calling the titular Blue Butterfly "the stuff that dreams are made of". This also references the fact that.
 * In "Once Upon a Crime", an episode about fairy tale-related crime, Beckett asks Esposito to look into a victim's bank account. He responds with, "As you wish".
 * In the episode "Eye of the Beholder" there's a thief named Serena Kaye, a reference to Cat Woman aka Selina Kyle
 * From the other direction: sister ABC show "Missing" featured a former CIA agent who became a successful writer of spy thrillers in the episode "Tell Me No Lies". One of the characters tacks a glance at the back cover, which has a recommendation quote by Richard Castle. Apparently, he's a fan.
 * Show Within a Show:
 * "The Late Shaft" - Bobby Mann Live is a mashup of the Letterman/Leno/Fallon late night TV shows, where the host Bobby Mann (played by Tom Bergeron) is the Victim of the Week
 * "One Life to Lose" - Temptation Lane is a shoutout to daytime soaps.
 * Shower Scene: Beckett gets one in Tick Tick Tick. The scene has many variants of the trope; the shower silhouette, the in-shower cam, the leg washing, the stepping into a towel, etc. It gets hot.
 * Shown Their Work:
 * Castle researches the material in his books before he writes them so as to present an accurate depiction of the subject matter. However that doesn't stop him from taking Artistic License with certain subjects.
 * In one episode, a killer was said to have been synthesizing cyclonite (AKA RDX) from formaldehyde. While formaldehyde is not a directly used in the synthesis, it is used to manufacture of the reagents used in synthesis. A sort of pre-precursor if you will. It was pleasantly surprising that the writers bothered to give a plausible method.
 * In "Wrapped Up In Death", the producers used a bio lab tech to show that they know what Carbon-14 dating is (unlike some other shows), and why it would work on mummies...and why it wouldn't work with the mummy in question.
 * In "The Late Shaft," Lanie gets a chance to explain MAO Inhibitors, and that you shouldn't take anything fermented with it (especially not balsamic vinegar).
 * In the season 2 finale, a bullet fragment is said to have been fired through a polygonal rifled barrel, such as those found in Glocks. Not only would it actually be possible to discern that from a bullet fragment, Glocks actually are one of the most common handguns to use polygonal rifling.
 * In "Punked" the writers managed to accurately portray Steampunk, actually contracting many professional Steampunk costumers for the club scene and having Castle deliver a very accurate summation of the philosophy of the subculture. This was especially rewarding after the Did Not Do the Research equivalent in NCIS Los Angeles.
 * "Last Call" gives us a pretty detailed history of New York during Prohibition, where there were a lot of speakeasies, supposedly because Mayor Jimmy Walker was an opponent of Prohibition.
 * Single Tear: Ryan is the only one crying when they meet in "Knockout",  A perfect single tear rolls down his face.
 * Sleep Cute: Episode "Close Encounters of the Murderous Kind" Rick Castle and Detective Beckett wake up in her police car after they were taken, interrogated then drugged by mysterious government agents. Later they are asked "Are those hickeys?" "They're from the injectors" he answers.
 * And again at the very beginning of "Cuffed", before they realize that they were--yet again--kidnapped and drugged.
 * Slut Shaming: Beckett is happy to shame the show's resident slut, Castle, who shrugs it off with good grace. See also: Urban Legend Love Life.
 * Smug Snake:
 * The killer,, in "Tick... Tick... Tick... / Boom!" -- he clearly wants to be a Magnificent Bastard and spends most of the multipart episode one step ahead of the police and the FBI, but this is more than balanced out by his tendency towards Villainous Breakdowns whenever things go against him and his general slimy, arrogant know-it-all demeanour.
 * Simmons, the drug lord Beckett brings in to ask about her mother's murderer in "Knockdown".
 * The little bastard from "Hedge Fund Homeboys". Both Castle and Beckett really, really want to take that punk down.
 * Sniff Sniff Nom: In "Murder Most Fowl" Castle finds a feather in the victims pocket, sniffs it, licks it and then declares that it's from a bird of prey. He also concludes that therefore, the man must have been killed by the nefarious "Falcon Killer".
 * Sniff Sniff Nom: In "Murder Most Fowl" Castle finds a feather in the victims pocket, sniffs it, licks it and then declares that it's from a bird of prey. He also concludes that therefore, the man must have been killed by the nefarious "Falcon Killer".

Everyone else: (incredulous look)

Beckett: Don't ask."

"Beckett: I gotta call my dad! [disappears offscreen]"
 * SoCalization: In "The Third Man", in Alexis' jealousy over her father's attention, she mentions that her classmate wants him. She then says that she's seventeen, "but she'll be legal in three months!" The age of consent in New York is seventeen.
 * Something They Would Never Say:
 * "3XK": Castle tells his mother he loves her while being held at gunpoint. Five minutes later, he's rescued.
 * Inverted in 'Countdown' --
 * Sorting Algorithm of Mortality: Lampshaded by Ryan to Esposito in "Under The Gun" who comments that because Esposito is snarky and Hispanic, he'll definitely die first. Castle tries to lampshade it but Beckett cuts him off.
 * Soundtrack Dissonance: In quite a few intros where the camera pans down to a corpse, relatively light music can be heard playing the background. Especially dissonant in the intro to "Home is Where the Heart Stops" with that cheery little pop playing as the camera slowly pans to the body.
 * Special Edition Title: "Countdown"'s title sequence is simply the logo, unanimated and tinted blue, to prevent Mood Whiplash.
 * "Kick the Ballistics" has the logo in normal colors, but no cheery music, again to prevent whiplash.
 * "Demons" has a Halloween special version of the intro, with the piano music played via Ominous Pipe Organ and wolves howling.
 * "Blue Butterfly" has the tune played in sax, jazz style.
 * "Always" has the logo in slighly greener tones, without cheery music.
 * Special Guest:
 * Joe Torre, a baseball player and manager. Castle is fairly nonchalant, having met Joe before and not being overly interested in the game anyway, but Beckett can barely keep from Squeeing and immediately rushes off to call her dad to gloat.
 * Chef Rocco Dispirito appeared in "Food to Die For" during Castle’s date with Beckett's high school BFF.
 * Spit Take: In Nikki Heat, Beckett sprays her coffee in reaction to Natalie's question
 * Squee: What Beckett tries (and partially succeeds) at holding in when she meets "Joe Frickin' Torre" in "Suicide Squeeze".

"Castle: Oh, and one more thing; one day, and one day not very far from now, I'm gonna use this in a book."
 * What most fans went through
 * Stab the Scorpion: A double Stab the Scorpion. Beckett and Castle are facing each other, both apparently pointing guns at the other. They fire simultaneously, and both hit a bad guy that was sneaking up to take the other unawares.
 * Stalker Shrine:
 * Castle's obsessive fan in "Flowers For Your Grave" possesses one of these, which goes a long way towards putting the nails in his coffin when it comes to his guilt.
 * Beckett Nikki Heat's obsessive fan in "Boom!" has one as well, complete with creepy Beckett Heat collage and manuscripts about killing Beckett Heat.
 * In "Inventing the Girl" the victim's stalker does not have one of those,.
 * Start to Corpse:
 * Zero in season 1 (the first shot of each episode was the corpse); not too much longer after (with a Law and Order cold open to start each ep)
 * Slightly extended in "Wrapped Up in Death," the first Castle episode to show the victim shortly before his murder actually being murdered by a sawed-off gargoyle head, then cut away to Castle's home antics, then back to the crime scene.
 * Extended a bit longer in "The Late Shaft", wherein the opening is Rick Castle going on a late night talk show, then the next morning finding out the host is dead.
 * Stealth Hi Bye:
 * "Home is Where The Heart Stops" Spoilered not to ruin the awesome.
 * In "Fool Me Once", the scary CIA agent does the same.
 * In "Knockout",
 * Steampunk: Castle and Beckett visit a Steampunk club in Season 3's "Punked." And it's awesome.
 * Strangers On a Train Plot Murder: "The Double Down." Both the movie and the original book are referenced. In this case, the strangers were on a boat.
 * Stunt Casting:
 * New Old Flame Kyra Blaine, played by Alyssa Milano. Oh, and Sophia Turner, played by Jennifer Beal.
 * The two-episode arc, Tick, Tick, Tick and Boom has Desperate Housewives' Dana Delaney as a federal agent. Nathan Fillion previously played Delaney's husband on that show.
 * "The Late Shaft" features Tom Bergeron, who just happens to host Dancing With the Stars, Castle's lead-in.
 * Averted with Beckett's dad, who's just a regular character actor and even matches the photo shown in passing during the first-season.
 * Lyle Lovett as a member of The Men in Black in "Close Encounters of the Murderous Kind".
 * Adam Baldwin in "Headhunters". The ABC press release prior to the episode made gratuitous mention of his past in Firefly, the beloved but short-lived show with Nathan Fillion. Baldwin also did numerous interviews promoting his one-episode part before the show aired.
 * Supporting Protagonist: Despite being the eponymous character, Castle is clearly this to Beckett. Looking at the tropes, he is the zany sidekick and she is the hardboiled detective who'd be the star of any other show. And the Sherlock Holmes comparisons abound: Castle finds Beckett, realises that she's a brilliant detective, all but attaches himself to her hip and then writes about their adventures in crime-solving.
 * However, the show operates on two levels. In addition to crime-fighting, the relentless UST between Castle and Beckett also prompts major character development from Castle. Even as he's the plucky sidekick in the cases, he's the main character in his transformation from playboy to heroic figure.
 * Sure Let's Go With That: Seemingly played straight in one episode where Beckett accuses Castle of messing with her chair while Castle thinks she's talking about him seeing the suspect behind her back. Castle thinks he's in the clear when Beckett shows that she knows about that too.
 * Switched At Birth:
 * Tag Along Author:
 * The premise of the show, with Castle shadowing Beckett for research and inspiration for his Nikki Heat novels.
 * Also invoked in-universe with an actual actor when Natalie Rhodes spends a case shadowing Beckett.
 * Invoked again, when writer Alex Conrad (Castle's protege) starts meeting with Beckett in "The Dead Pool".
 * And yet again, in "Heroes and Villains", when Paul Whittaker turns out to be a journalist shadowing costumed superhero Lone Vengeance.
 * Averted in "Ghosts". Ghostwriter Lee Wax tried to arrange an all-access pass with Castle. But when Castle figured out that  her all-access pass was revoked. And to add insult to injury:

"Castle: How about: "A whole new chapter in crime-solving". "Chapter", get it?
 * Tagalong Kid: Sometimes Alexis. She's smart and mature and all that, but still unquestionably a kid. And on those occasions when she shows up at the precinct, everyone's on their best behavior.
 * She gets to do a lot more tagging along now that she works for Lanie.
 * Tagline: In-universe example in the episode "The Late Shaft", Castle decides he and Beckett need one. He first tries "She's armed, he's dangerous" without success, then...

Beckett: Ooh! ... No."

"Castle: This guy is like Indiana Jones but with space age technology. Oh, which would have been such a better movie than that last one."
 * Take a Third Option: A dog, of all things, gets to do this in "An Embarrassment of Bitches" when, given the choice of living with Castle or Beckett, who have been sharing responsibility of taking care of him,
 * Take My Hand: In "Always":
 * Take That:
 * In the episode "Wrapped up in Death" a archeologist at a museum is killed and an ancient Mayan mummy curse is blamed. Not much later this happens:

"Castle: Should I be flattered or insulted?
 * In "Sucker Punch", Beckett mentions that the Captain's post-incident evaluation has Castle come off like Steven Seagal.

Beckett: {chuckle} Both."

"Sorenson: Why the sudden need to shadow a real detective ?
 * In "Little Girl Lost", we have this exchange between Beckett's ex-boyfriend and Castle.

Castle: Well the ones on TV seem mighty fixated on their sunglasses."

"Castle: Do I see two guys going out on a hot workman-related case? That sounded dirtier than I thought."
 * Taking You With Me: How ends season three.
 * Tempting Fate: a hilarious one on Chapter 1, nonetheless. Castle is talking to Alexis, telling her he wishes for someone to come to him and say something new. When Beckett appears and tells him she wants to question him about the killings by someone who is making his killings look like Castle's books, Alexis lampshades the whole thing.
 * Ten Minute Retirement: "Sucker Punch", of a sort;
 * Ten Paces and Turn: "Punked"
 * That Came Out Wrong:
 * One slightly different instance comes in "Almost Famous". Castle talks about pumping Manschaft until he pops. There are very quick cuts showing reaction shots before the scene moves on. Though from Castle's tone, it's more a matter of Getting Crap Past the Radar.
 * This brief pip from "The Final Nail":

"Castle: You should really moonlight [as a dominatrix]. Trust me -- you would make a fortune. Come on, isn't there anything you would like to do with your handcuffs besides arresting criminals?
 * The Big Damn Kiss:
 * The Tease: Beckett takes great amusement in leading on Castle's obvious attraction to her, only to bluntly shoot him down. Lampshaded in "The Mistress Only Spanks Twice":

Beckett: No...[seductively] but there is one hot, wild, kinky thing that I do like doing...

[Castle's elbow slips off the table as he stares at her earnestly]

Beckett: [Flatly] Putting killers behind bars.

Castle: [Disappointed] See, you're already a tease—you're halfway there."

"Castle: Where was the badge?
 * Turns against her when he
 * Theme Tune Cameo:
 * In "Home is Where The Heart Stops", Castle is sitting alone in the car humming his own action-scene Leitmotif. When the bad guy shows up to hijack the car and drags Castle into a fistfight, he stops humming and the leitmotif starts playing over the scene.
 * When Castle walks into the The Old Haunt in "Last Call", the bar's piano player starts playing that leitmotif again. Castle even thanks the piano player for remembering and tips him.
 * They Fight Crime! He's a lecherous mystery novel writer! She's an uptight police detective!
 * Those Two Guys: NYPD detectives Javier Esposito and Kevin Ryan that Kate works with. It wasn't until "When the Bough Breaks" (the fifteenth episode) that we saw those two apart for even a moment.
 * Not quite true -- since Ryan wasn't originally supposed to be a character, there are some moments in the pilot when Esposito is walking around with some other random detective. Ryan's absence is VERY noticeable when you rewatch it after a few other episodes.
 * In "The Blue Butterfly", they play Those Two Bad Guys in the flashbacks (Castle's imagination as he reads a diary from the 1940s).
 * Time Bomb:
 * Title Drop: Episode titles are dropped quite often, because they either would make great names for Castle novels, or already are great names for Castle novels.
 * Except for an offhand lewd remark in one episode, there is no buildup to this which is lampshaded by several jokes in the vein of "Can you believe they still think we don't know?"
 * Tonight Someone Dies: Promos for "Knockout" used a Castle line "One of them is gonna die."
 * Tragic Keepsake: "A Chill Goes Through Her Veins" reveals that Beckett wears her mother's wedding ring as a reminder of "the life I lost". Also inverted, in that she also wears her father's watch to remind her of 'the life I saved'; she helped him recover from alcoholism and grief after her mother's death broke him. Because the latter's more visible (and unusual), Castle mistakes it for the former.
 * Treachery Cover Up: The team agrees to hide shameful past after his death at the end of the third season.
 * The Triads and The Tongs: The team's investigation of 3xK leads them to a tong. Beckett mentions that most tongs are legitimate merchant organizations but a few are involved in criminal activity.
 * Triang Relations: It starts with a Type 5 in "Den of Thieves,", and either Type 4   or Type 10   at the end of the Season Two finale.
 * Trouser Space/Victoria's Secret Compartment: In "Home Is Where The Heart Stops", Beckett has to make an arrest while at a black-tie event, wearing a rather skimpy dress.

Beckett: Don't ask."

"Beckett, to Ryan, Esposito, and Castle: No one — no one outside of this immediate family, ever needs to know about this."
 * True Companions: Settled in the third season finale:

"Beckett: Now that you mention it, he looked terrified. And this whole time I thought he was scared of me."
 * Turn in Your Badge:
 * Though no actual badge-turning occurs, Montgomery sends Beckett home after she roughs up a witness in "Knockdown". Then he sends Castle home, too.
 * Fallon does something similar in "Setup."
 * In the episode "Always"
 * Twerp Sweating:
 * Averted in "A Death In The Family" -- Castle wants to scare Alexis' date with a fake severed head, but she cuts him off at the pass. Lampshaded in the same episode when Castle and Ryan reminisce about the ways the fathers of their prom dates had done this, leaving the previously clueless Beckett to come to the dawning realisation that this was what her dad was doing when she was upstairs getting ready for her prom.

"Beckett: I contacted other precincts to find out who else is investigating her and for what.
 * Castle later pulls this off pretty well, mostly by accident, in "Punked." He
 * A deleted scene from season 3 has Jim Beckett inadvertently do this to Castle. And it is magnificent.
 * Twin Threesome Fantasy: An actress who has been studying Beckett in order to better portray Nikki Heat (in the episode of the same name) gets a delivery that's "supposed to help with [her] research," then goes to change. A couple of scenes later...

Rhodes: (walks into the room with Beckett-styled wig and pantsuit) Talk to enough people, something usually shakes out.

Castle: (pencil falls out of hand, as Beckett stares at Rhodes) Just like I dreamed it...!

Beckett: (GLARES at Castle)

Castle: ...Did I say that out loud?"

"Rhodes: I don't get it. He's into you, but you're determined not to give into these feelings that you clearly have for him, so he fantasizes about you through his writing. It's literally verbal masturbation."
 * Two Lines, No Waiting:
 * Subverted in "The Double Down", it seems as though two investigations are going on at the same time, but then they turn out to be connected.
 * "The Fifth Bullet", as well, although it takes all of five minutes for them to connect Riley Amnesia Guy to the murder.
 * Tyrant Takes the Helm: In comparison to Montgomery, Victoria "Iron" Gates fits this trope to a T.
 * Uncle Pennybags: Though used variously in the earlier seasons where Castle would use his wealth and influence to do something, as of the later seasons, this aspect of his character has been heavily downplayed. Likely due to the show really hitting it's stride and not needing such exaggeration.
 * Still referenced in Season 4; when Castle first reads the bill for his actions during "Eye of the Beholder", his only response is to say it's "a good thing he's rich".
 * Undercover Model: Kate Beckett does this impromptu-ly around Russian mobsters. More specifically: she ditches all clothing bar (bright red) underwear and a trench coat.
 * Undying Loyalty: "Knockdown" makes this almost painfully clear.
 * Unrequited Love Switcheroo: Seems like every third episode, now. Just as Beckett gets over Demming, here comes Castle's ex-wife. And just as Castle's done with his ex-wife, here comes Marty Stu Josh.
 * Urban Legend Love Life: Despite the claims of his Casanova charms, Castle has only been shown to be having sex with three women, two of whom were ex-wives (and one of those ex-wives is also his editor.) Probably because the writers want to get him together with Kate and they can't do that if he's sleeping around a lot. Probably also because while Castle may enjoy the flirting and the dating, he actually doesn't seem too interested in the sexing part unless it's actually with someone he connects with.
 * Conversely, Beckett is shown or mentioned to have dated a number of men; more than Castle has dated women. While this doesn't necessarily translate into a love life (since it's also mentioned she doesn't really connect with people well), it's suggested that she intentionally self-sabotages relationships by dating for the short term and dating people she knows aren't ultimately compatible. Refreshingly though the show makes no comment on the matter of sex and romance for a female lead and simply treats it as the activities of a normal adult.
 * UST:
 * The show manages to up the ante on shows like The Nanny and Bones by having Castle more or less repeatedly go to Beckett "So! When are we sleeping together?"
 * In 2x13, "Sucker Punch", Beckett refers to Castle "pulling her pigtails"
 * In 2x14, "The Third Man", ends with Castle and Beckett walking out of the police station arm-in-arm to head to a burger joint after their fancy dates (with other people) fall-through due to the case-of-the-week. As they walk, Beckett is playfully twirling her hair with her finger, something that Castle had noticed her doing earlier while talking to her date on the phone.
 * 3x05, "Anatomy of a Murder", had Castle comments to Esposito about how true friends will help you break out of jail. Beckett casually walks by and comments that she'd spring him, and the look on Castle's face is absolutely priceless. Also, the Love Letter Lunacy played for epic amounts of Ship Tease in the same episode...GAH!
 * Castle's reaction to Beckett's comment is much bigger than what it looks like, because his mother told him before that breaking a loved one out of jail was an act of pure love.
 * 3x11, "Nikki Heat", has a With This Ring moment where Castle casually offers an engagement ring to Beckett and asks her to marry him. Subsequently, an actress studying Beckett to portray Nikki Heat hangs the biggest lampshade ever as she spells it out, word-for-word, to Beckett:

"He's sweet on you. Makes him brave."
 * 3x13, "Knockdown". The guys bring a Genre Savvy Smug Snake into the interrogation room. Aside from being entirely unflappable, he figures out Castle likes Beckett within seconds.

"Castle: Yes. Fine, it's true. I'm jealous. There, I said it. I-I want you all to myself, and to have you spending time with another writer? That upsets me! And if that makes me petty, so be it. Guilty as charged.
 * 3x21, "The Dead Pool". Castle confesses his jealousy when Beckett starts spending time with another writer.

Beckett (smiling) : Actually, I kinda think it's sweet.

Castle: You do?

Beckett: I do. And that's why you don't have to worry about me hanging around with Conrad anymore. From now on I'm a "one writer" girl."

"Kate: You're staying here.
 * Vanity Plate: In a rather touching tribute, the show used the late Stephen J Cannell's Vanity Plate at the end of "Punked".
 * Vigilante Man: Seemingly, the murderer in "Heroes and Villains"
 * Voiceover Letter: See Dead Man Writing.
 * Wacky Parent Serious Child: Richard to Alexis, and to a slighter extent, Martha to Richard.
 * Wait Here:
 * Castle, natch. Happens so frequently that it borders on Running Gag. The few times where Castle listens and does stay, the bad guy runs by him or otherwise gets Castle involved anyway.

Castle: Yes, we've seen how well that works out."

"Castle: Now you know what it's like for me."
 * There's also the time in the pilot when Beckett handcuffs him to the squad car, and he gets hijacked by the suspect.
 * Subverted in "Boom!", in which Kate hands Castle a gun as they go to bust the killer, and Castle just stands there in disbelief for a second.
 * Earlier in "Boom!", Beckett is told to wait in the van (since the killer is specifically looking for her):

"Martha: Richard, this isn't one of your books. You don't know the ending. You were just lucky yesterday.
 * Western Terrorists: In
 * In "47 Seconds" the chief suspect in the bombing of a Takeover Wall Street protest was a right-wing activist.
 * Wham Episode:
 * "Sucker Punch", where
 * "Knockdown", where
 * "Knockout", where
 * "Always". Good God, "Always". Every constant this show has has just been turned upside down.
 * Wham Line: In "Rise", Beckett tells Castle that she doesn't remember anything about season 3 ending. At the end of the episode, she tells her psychologist that she actually remembers everything that happened.
 * In "Linchpin", "Your father will be very proud."
 * And again in 47 Seconds, where she tells a suspect that claims to have amnesia that she, with Castle listening behind the one-way mirror, in a moment of self-inflicted Engineered Public Confession. Castle goes on Passive-Aggressive mode the rest of the episode, as a result.
 * "Always".
 * What the Hell, Hero?: Martha deals one of these to Castle in "Knockdown," during a rare Mama Bear moment.

Castle: You're overreacting, mother. Where is this coming from?

Martha: (incredulous stare, tearing up) How the Hell can you ask me something like that? Think about how much you love Alexis and that is how much I love you and don't you dare ask me where this is coming from! (calming down) You have gotten through most of your life on your wit and your charm and no small amount of talent, but that is the real world out there. And you can't charm your way out of a bullet."

"Castle: Alright, y'know what? I don't know what we are. We kiss and then we never talk about it. We nearly die frozen in each others' arms but we never talk about it. So no, I got no clue what we are."
 * Again in "Knockout" with Castle calling Beckett out for her Will They or Won't They? behavior:

"Beckett: Wow, Castle, that's... a refreshingly down-to-earth theory.
 * Lanie calls Beckett out in "The Limey" for not telling Castle what she feels for him, and about the fact that she knows he loves her.
 * White Dwarf Starlet: Castle's mother.
 * White Gang Bangers: The Westies, an Irish gang in NYC, make multiple appearances.
 * Wild Teen Party: In "Heartbreak Hotel", Alexis watches in slowly growing horror as one of these takes place in her own home. In a variation, she acknowledges that her father probably won't care, but the problem is that she does.
 * Will They or Won't They?: Definitely: Leaning towards "they will". And doesn't Castle know it. During one case they get asked if they're together, to which Beckett responds "No." Castle's simultaneous response? "Not yet."
 * Wire Dilemma:
 * Women Are Wiser: played with; Alexis is a lot more grounded and mature than her father is, but compared to his ex-wives and to a (slightly) lesser extent his mother, Castle himself is a bedrock of maturity, common sense and selflessness.
 * Won't Take Yes for An Answer:
 * Variation in "Law and Murder": Captain Montgomery pulls Beckett and Castle in asking them why they pulled the DA's secretary in without the DA's knowledge. Beckett starts to apologize, but Montgomery cuts her off...with "Smart move."
 * In “Knockout” Beckett goes to Captain Montgomery to tell him, fully expecting to hear that it isn’t possible because of , and starts vehemently arguing her case only to realize he agreed. Her flustered response is all the proof he needs that she wasn't serious and was just venting.
 * Working the Same Case: "The Double Down"...which does nothing to dull the wager on whether Castle & Beckett or Ryan & Esposito will solve their case first.
 * Wounded Gazelle Gambit:
 * Done to Castle in "Love Me Dead". He finds it discomforting that someone could tell him a story and make him believe it and that someone was able to take advantage of his hidden heart of gold. Especially since the person doing the gambit
 * Also in "The Late Shaft", he floats Beckett's suspicion that an actress is only sleeping with him to get the Nikki Heat part in the Heat Wave movie, and she breaks down in tears.
 * Perhaps a Brick Joke as of "Nikki Heat" when we meet the actress who plays Nikki Heat in the movies.
 * In "Cuffed", one of the criminals
 * Write Who You Know:
 * Castle's new main character, "Nikki Heat," is Beckett. To the point that when Beckett showed up at his launch event, the photographers said "It's Nikki!" In the actual Heat Wave, "Nikki" has Those Two Guys on her team: Raley and Ochoa, usually combined to "Roach." And she's being shadowed by a writer (this time, a reporter) who pulled strings with the mayor's office to get himself attached to her. Named Jameson Rook. Except Nikki and "Rook" had sex in the book -- Castle has less patience than his show's writers, it seems.
 * In the episode "Boom", where the FBI and NYPD teams find an autographed copy of Heat Wave that says, "To Scott: Write what you know." "What he knows" turns out to be  The same guy
 * Wrong Genre Savvy: Played for laughs.
 * Castle likes to latch onto unusual facets of the case and build absurd plots out of them, when the truth is inevitably more straightforward:
 * Castle spends the first few minutes of "Vampire Weekend" running around as if he's actually in a vampire movie.
 * "Close Encounters of the Murderous Kind": Every single one of his theories points to aliens, and almost gets Beckett to believe it, too..
 * In "Poof! You're Dead" Castle constantly -- and incorrectly -- assumes that various 'magic story' twists are in effect.
 * In "One Life To Lose", a murder on the set of a soap opera leads Castle to come up with an endless list of over-the-top soap opera style plots as potential theories behind the crime. Which leads to this moment when he comes up with a more plausible one for once:
 * In "Poof! You're Dead" Castle constantly -- and incorrectly -- assumes that various 'magic story' twists are in effect.
 * In "One Life To Lose", a murder on the set of a soap opera leads Castle to come up with an endless list of over-the-top soap opera style plots as potential theories behind the crime. Which leads to this moment when he comes up with a more plausible one for once:

Castle: Just trying to keep you on your toes."

"Nathan Fillion: You've got one line.
 * In "A Deadly Game", when "Hans Rowr" is arrested, he claims he'll soon be bailed out by powerful superiors to escape as a Karma Houdini
 * Yandere:
 * In 1x02, "Nanny McDead", the killer ended up being
 * In 2x16, "The Mistress Always Spanks Twice", the killer turned out to be
 * In 3x12, "The Final Nail", the killer was
 * You Called Me "X" - It Must Be Serious: Castle hardly ever calls Beckett by her first name; it's warranted only for a special, dramatic occasions.
 * Once in "Sucker Punch,".
 * The second and third time happen during the two parter "Tick, Tick, Tick..." and "Boom!",  and , respectively. He also calls out her name a few more times (five more times, if you want to be precise).
 * Once more in "Knockdown,".
 * Beckett also calls Castle 'Rick'
 * And Castle calls Beckett 'Kate'
 * The 'Kate' and 'Rick' quotient is upped in "Knockout", culminating in
 * Also occurs with...
 * During Rise, Castle ONLY calls Beckett 'Kate'.
 * In "Kick the Ballistics", Castle calls Ryan by his first name once... at the end of the episode, when he is reassuring him about how he did the right thing.
 * In "Kill Shot," Beckett calls Esposito "Javi" when he's trying to help her past her PTSD. She also calls him "Espo".
 * In "Always," Ryan and Esposito call each other Javier and Kevin when Detective Ryan expresses concern that the team is following the wrong course of action.
 * You Do NOT Want to Know: Inverted in "Heartbreak Hotel." Ryan and Esposito try to explain why they're wearing Elvis costumes, but Beckett decides she doesn't want to know.
 * You Have Outlived Your Usefulness: In "Cops and Robbers"
 * You Have No Idea Who You're Dealing With: Beckett tries this in "Always".
 * Your Mom:
 * During the outtakes, Jon Huertas apparently screwed up his line and this happened:

Jon Huertas: Your momma has one line."

"Esposito: OKAY!
 * Comes up again in "Knockdown", when :

Ryan: Don't tell this jackhole anything.

Esposito: I'm sorry, bro, I can't watch this. (to interrogator) Listen to me! You're too late--the cops already know all about... me and your mom."


 * Your Princess Is in Another Castle: One of Castle's main skills appears to be spotting where these moments are coming up.
 * He keeps investigating the case in the pilot precisely because his writer's sensibilities are offended by the 'easy' solution to the mystery ("the reader would never buy it!"). This occurs exactly half-way through the episode.
 * In "The Mistress Always Spanks Twice,"
 * In "Boom!", he's able to sniff out a trap due to this very reasoning.
 * In "Setup", Castle is pretty much the only one who believes that, and Beckett the only one who'll hear him out. He turns out to be right.
 * In "Slice of Death",
 * Zany Scheme: Castle comes up with a fairly straightforward one in Heartbreak Hotel. Results in Castle, Ryan, and Esposito  in Elvis impersonator costumes.
 * Averted (kind of) in "The Limey". Castle's plan is outlandish even for Castle, but Beckett cuts him off with a Zany Scheme of her own. She'll get the fingerprints the easy way... by gatecrashing an exclusive dinner reception at the British Embassy.
 * Zorro Mark: In "Heroes & Villains", the vigilante Lone Justice carves an 'L' into the butt cheek of a mobster with a sword.