Subverted Catchphrase

A character appears to be setting up their Catch Phrase, but instead says something completely different. Almost always a comedy trope, where the humour comes from subverting the audience's intentions.

Film
"Jack Slater: I'll be back! Ha! You didn't know I was gonna say that, did you? Danny Madigan: That's what you always say! Jack Slater: I do?"
 * Last Action Hero:

"Jack Slater: You've seen these movies where they say, "Make my day," or "I'm your worst nightmare"? Well, listen to this one: Rubber baby buggy bumpers!"
 * And later in the same film:

Game Shows

 * Occasionally done for laughs on Jeopardy! when someone hits a Daily Double. Instead of saying the typical "I'd like to make this a true Daily Double", one contestant said, "I'd like to solve the puzzle." The requirements for answers being a question have also been abused for jokes, such as "What be ebonics?"
 * Contestants on other shows have to be reminded that they're not on Jeopardy! (Gambit, Win Ben Stein's Money) after answering a question in the form of a question. Ben Stein makes a causer of this infraction wear a dunce cap.
 * Late in the run of Classic Concentration, contestants started saying "I'd like to solve the puzzle" once the board was at a position where the rebus was solvable.

Live Action TV
"Barney: You are legen- wait for it - daddy, legendaddy."
 * Fez of That '70s Show is prone to saying "Good day," to which another character protests, "But, Fez..." and he replies, "I said, 'Good day,'" and storms off. On a few occasions, however, he subverts the expectation by either not responding to the "but" line in the same manner, or else replacing "good day" with another phrase, often something to do with candy or women.
 * Barney from How I Met Your Mother did this once.

"Spock: Most illogical. Of all people, he should have known how the computer would perform. Of course, the M-5 computer itself has not behaved logically. McCoy: Please, Spock, do me a favor, don't say it's "fascinating". Spock: No, but it is interesting."
 * In Star Trek: The Original Series, Spock would often say, "Fascinating!" in response to something odd or perplexing. However, in "The Ultimate Computer":

Video Games

 * Whenever Kenny dies in the South Park cartoon, someone (usually Kyle, Stan, and/or Cartman) will shout, "Oh my God! They killed Kenny! You bastard!" However, in the game South Park and the Stick of Truth,

Web Original

 * The Nostalgia Critic does this a lot. Every once in a while, instead of his normal catch phrase ("I remember it so you don't have to."), he'll say something else instead, generally indicating the covered work is really bad instead of just plain old bad. One example comes at the end of his review of A Kid In King Arthur's Court, where he hits himself with a book in an attempt to forget the awful movie. As a result, he finishes by saying "I remember it so you don't Blue's Clues."
 * Another example occurs in his top eleven lists("Why top eleven? Because I like to go one step beyond.") In Top 11 Disney villains: "Why top eleven? If you don't know by now, kiss it." And in Top 11 Coolest Cliches: "Why top eleven? Because I have my own cliche that'll never die."
 * NC has gotten a lot of use out of a clip of M. Bison turning around and shouting "OF COURSE!" whenever mention is made of taking over the world. When he dons Bison's trademark outfit in Kickassia, Chris Larios asks if he's planning to take over the world, and he turns and shouts, "NATURALLY!" However, after a few more tries, Larios does get him to deliver the line he wanted.
 * But only by asking him if the outfit gets him laid.
 * Linkara has probably subverted his "Because poor literacy is kewl!" Running Gag more times than he's played it straight.
 * And at least twice, he's subverted "This comic sucks!" when it turned out that the comic didn't suck.

Western Animation
"Benson: Muscle Man, have you seen Pops at all today? Muscle Man: Yeah, and you know who else has seen Pops today? Benson: (dryly) Who, your mom? Muscle Man: I wasn't gonna say that! Why does everyone always think I'm gonna say "my mom"?"
 * On an episode of Regular Show, Muscle Man subverts his "MY MOM!" catch phrase:

"Muscle Man: You know who taught him? My Uncle John. He's a mechanic[…]You know who taught him? MY MOM!"
 * And a Double Subversion, when asking if they know who taught High Five Ghost his mechanic skills:

"Pinky: What are we gonna do tomorrow night, Brain? Brain: The same thing we do every night, Pinky... I have absolutely no idea. Pinky: Poit. Brain: Narf."
 * At least once on Adventure Time, Finn and Jake have subverted their "What time is it?" "Adventure time!" exchange.
 * In the Pinky and The Brain episode "That Smarts", the Brain's attempt to make Pinky smarter eventually leaves them both stupid. They attempt their usual So Once Again the Day Is Saved:

"Stan: Welp, we killed Kenny. Kyle: Yep, we're a couple of bastards."
 * There are also two or three occasions when Pinky actually is pondering what Brain is pondering, instead of giving his usual response of "I think so, Brain, but..."
 * As stated above in "Video Games", the usual reaction to Kenny's death in South Park is "Oh my God! They killed Kenny! You bastards!" However, Kenny's death has been a Running Gag for so long, the Trope is applied now and then:
 * In one episode, before Stan can say the "You bastards!" part, Wendy frantically asks him who "they" are. He's at a loss to answer.
 * Another late-season episode where Stan and Kyle clearly can't fake being surprised anymore:


 * In episode 10 of Scooby-Doo! Mystery Incorporated, Scooby is locked up in an animal asylum, framed for attacks made by a robotic lookalike. Shaggy is despondent, so Velma attempts to cheer him up by wolfing down a sandwich and saying "Relma Delma Doo!"
 * Phineas and Ferb does this almost Once an Episode.
 * "Aren't you a little old to be building a fort?" "No, no I'm not. Shut up."
 * "Aren't you a little old to be a heavyweight boxer?"
 * "Aren't you a little young to be toy designers?" "No, I don't think so."
 * "CURSE YOU, INADEQUATE IMMUNE SYSTEM!"
 * "CURSE YOU, MOTOR-VEHICLE CODE!"
 * "CURSE YOU, PERRY THE PLATYPUS BALLOON!"
 * "BLESS YOU, PERRY THE PLATYPUS!"
 * "PERRY THE BANJO-PLAYING PLATYPUS!"
 * "PERRY THE PLATYPUS BALLOON!"
 * "PERRY THE TEENAGE GIRL!"
 * "Norm, I know what we're going to do today!"
 * Futurama sometimes does this with Farnsworth's "Good news, everyone", instead having him say something like "Bad news, no one" or "Good news, no one".
 * Also, Hermes in "How Hermes Requisitioned His Groove Back": "Sweet... something... of... someplace". This counts as a subversion as well as a Lampshade Hanging, since it's the only time where it doesn't rhyme, and one of the only times when the "something" isn't an animal.