Examples:Anime and Manga
- After the first stage of the Chuunin exams in Naruto, Proctor Ibiki explained that there were two members of the test takers who served as cheating fodder for the others, which several shinobi noticed, but Naruto was not among them. However, once Ibiki explains this, Naruto acts as if he figured it out halfway through.
- In Pretty Cure All Stars DX 3, Cure Marine and Cure Rhythm start panicking when Cure White, Cure Egret, Cure Mint, Cure Aqua, and Cure Berry start taunting Freezer and Frozen. When it turns out that their taunting leads the two to freeze the water they were trapped around, Marine instantly declares that it was a great plan and she knew it all along. The others don't buy it.
- In the Donald Duck comic "The Old Castle's Secret", after the "ghost" is revealed to be a guy using invisibility spray, Donald tries to claim he knew it all along (rather than being terrified out of his wits while Huey, Dewey and Louie single-handedly solved the mystery themselves). His nephews are not amused.
- In The Little Mermaid, this was Scuttle's response after Sebastian tells him that Ariel had gotten legs (Scuttle knew that something was different about Ariel, but kept guessing right off the bat that it was something else).
- The Fugitive (1993): The U.S. Marshals are listening to the tape of Kimble's phone call to his lawyer. Several of them say they think that a sound on the tape is made by an elevated train, but Gerard disagrees and sarcastically abuses them. As they continue to analyze the tape they realize that Kimble was calling from Chicago near an elevated train line.
Gerard: I knew it was an elevated train.
- The Land Before Time: After Cera was cornered by a pack of Pachycephalosauruses that were scared off by a seemingly monstrous tar blob monster, she becomes afraid that the monster will get her too. However, the monster turns out to be Littlefoot and the others all covered with tar. Once Cera realizes this, she then proclaims that she knew all along that it was them.
- Lynch, Bud Fox's boss in Wall Street, tells him "The minute I laid eyes on you I knew you had what it took," when Bud's star is rising. When Bud is arrested, Lynch has his own personal retcon, saying, "The minute I laid eyes on you I knew you were no good."
- In Harry Potter and the Chamber Of Secrets, Professor Lockhart claimed, after Professor Snape hit him with a disarming spell during a demonstration, to have known what Snape was going to do, and that if he wanted to block it he could have.
- When Harry and Ron are hiding in the teachers' room and someone suggests a remedy for the students' petrification, Lockhart is heard to mumble something along the lines of "Of course, it's what I've been saying all along."
- Harry always assumed that Malfoy was working with the Death Eaters in Harry Potter and the Half-Blood Prince, in the end he was right. Except that Draco didn't exactly enjoy being a Death Eater.
- C-3PO says the line verbatim in The Empire Strikes Back, claiming he knew all along that Lando Calrissian was really on their side. Of course, this seems more like wishful thinking that just happened to be correct, since 3PO was already having a pretty bad day what with being dismembered and carried around on Chewie's back like a bookbag, and he really wanted to catch some kind of break.
- Amelia Peabody and her husband Emerson both like to claim to be better at detective work than they actually are:
- In The Curse of the Pharaohs, most of the "deductions" Emerson claims to have made were actually things he had no idea about until the killer confessed.
- In The Deeds of the Disturber, Amelia gives The Summation to their assembled friends, explaining why one person and one person only could be the mastermind behind the murders. When she and Emerson are in bed together later, however, they both confess that they had both suspected the wrong person right up until The Reveal.
- Buffy the Vampire Slayer: Willow, on learning of Xander and Cordy's makeouts.
Willow: I knew it! Well, not in the sense that I actually knew anything, but you two were arguing way too much!
- Most certainly NOT Played for Laughs in the Doctor Who episode Midnight. After claiming loudly and vocally that the Doctor was possessed by the entity and that he should be thrown out of the airlock, the mother weakly claims that she knew that it wasn't him all along. She wisely shuts up after the Doctor gives her a Death Glare.
- Rat in this recent Pearls Before Swine comic.
- Garfield did this lots of times, especially in this strip.
- Played for laughs in this video where someone plays Kirby Super Star and is terrified of Waddle Dee. A bystanding Straight Man makes some rational observations on him, all dismissed by the player as "Lies!" The friend eventually tells the player how to get Kirby to properly attack (to which the player expresses amazement), and once Waddle Dee finally dies, the player exclaims, "It worked! I'm a genius!"
- Woofer on Clue Club always brags to Wimper of how he knew who the mystery's culprit was and his modus operandi.
- In the Scooby-Doo, Where Are You! episode "Never Ape an Ape Man", Shaggy gets "grabbed" by a stuffed ape. Upon being told this, he says, "Well, I certainly hope you don't think he had me fooled for a minute. I knew it all the time." Scooby sees right through him.