Continuity mistake: The German and British airmen are looking at the Northern lights. From the rear the men are apart, but the front shots of them show them much closer to each other.
Continuity mistake: When the mean Santa puts the little girl in his lap and asks her what she wants, she's wearing gloves. When it cuts to a different angle, suddenly her gloves are gone.
Continuity mistake: The pile of notes on the floor near the end changes between the close up and long shots. (01:13:20)
Continuity mistake: Dinner at Forestier's home, and Georges Duroy does not know which knife to use to eat. The asparagi in his plate are across the small pie in the wide shot, and in close-up they are arranged entirely on the side without his intervention. (00:08:20)
Continuity mistake: In the car after Martin tells Hans about the throat slitting story, Billy and him get into an argument about the violence of the story. Billy says "It's going to be violent, it's about seven fucking psychopaths!" Martin then says "Hey!" But you can see in the back seat his mouth doesn't move for that. Then it cuts to a close up of Martin and his head is in a different position, facing Billy where he was looking out the window a moment before. (00:58:05)
Continuity mistake: The alarm clock chimes; Juno Temple reaches up with her left hand, putting it on the upper part of the pillow. Michael Angarano crawls over her to turn the alarm off, but she's napping with her hand by her chin, on the bottom corner of the pillow. (00:02:40)
Continuity mistake: Tom walks into Anthony's memory. Anthony is sitting by the pool next to a table with two glasses of beer, which are 1/3rd empty. A few minutes later the memory is replayed, but this time both beer glasses are mostly full. (00:49:50 - 00:58:35)
Continuity mistake: In the scene where Billy Crystal is chasing his grandson at the recital, he has day-glow paint on his face. A few seconds later in front of the stage, the day-glow paint is gone.