10 Best "Everything You Know Is A Lie" Moments In Movies
6. Leonard Accidentally Killed His Wife - Memento
Christopher Nolan's masterful Memento is an especially interesting case because the character in question actually deceives themselves, and does so totally intentionally.
Protagonist Leonard Shelby (Guy Pearce) is suffering from anterograde amnesia after a home invasion which apparently caused the death of his wife.
Leonard is unable to create new memories since the attack, and so uses polaroid photos and tattoos to keep investigating despite this.
But at story's end, we learn that Leonard's wife actually survived the attack, and only died after Leonard, while suffering from amnesia, accidentally gave her an insulin overdose.
Leonard has repressed this memory, and despite killing the real attacker before the film's events, has effectively concocted a cyclical revenge narrative in which he kills various shady figures, duping himself into believing them to be the assailant, in order to avoid facing reality.
It's perhaps cinema's finest example of self-deception, as even when acquaintance Teddy (Joe Pantoliano) reveals the truth to Leonard, it's information he's soon enough destined to forget.