Deliberate mistake: When Batman enters the replica of The Joker's apartment there's no place for The Joker to hide. Yet seconds after Batman enters, The Joker comes out of nowhere to hit him with a pot.
Batman: The Killing Joke (2016)
1 deliberate mistake
Directed by: Sam Liu
Starring: Tara Strong, Mark Hamill, Ray Wise, Kevin Conroy
Continuity mistake: When Batman and Batgirl are about to have sex on the roof, Batman lets his left hand slip down from her back to her butt. In the next shot, it's on her back again.
Bruce Wayne: All these years, and I don't know who he is any more than he knows who I am.
Alfred: Are you sure of that?
Bruce Wayne: What do you mean?
Alfred: I mean... Don't underestimate him.