How to Steal a Million (1966)

Continuity mistake: When Peter O'Toole is locked in the closet at the museum, he puts a rope through the keyhole and uses a hook to pull it under the door. In the first shot, from outside the closet, the end of the rope is to the right. In the next shot, from inside the closet, the end of the rope slides under the door to the left. (01:22:30)

Continuity mistake: When Peter O'Toole takes the Cillini and replaces it with a wine bottle, the bottle is about half full. When the guards finally realize that the Cillini is gone, the bottle is obviously empty. (01:39:15 - 01:42:45)