Sleepy Hollow (1999)

Revealing mistake: When the Headless Horseman is about to kiss Catrina's stepmother, you can see his actual teeth behind the filed ones. Christopher Walken's teeth are blacked out and their outline is visible against his tongue during the closeup of his face. (01:37:20)

Revealing mistake: When the whole town's in the church and Katrina's father gets the pole through his stomach, if you watch while he gets dragged through the graveyard, he hits a headstone and it moves back. (01:18:10)

Revealing mistake: In the scene where Ichabod and Young Masbeth enter the witch's cave, the witch tackles Ichabod to the ground. The creepy face of the witch is obviously a mask because you can see the black cloth where the eyes are if you pay attention closely.