BillyBlake

Revealing mistake: When Sollozzo picks up Tom Hagen after killing Luca Brasi, you can easily tell that the snow falling is made of thin plastic.

BillyBlake

Revealing mistake: When Michael is riding in the car with Sollozzo before the assassination, notice the headlights in the rear window during the close-up. You can notice that many of them move directly on top and underneath each other, impossible for real car's headlights to do such a thing. (01:21:25)

BillyBlake

Revealing mistake: When Vito Corleone is walking Johnny Fontane out of his office, he opens the door and you can see an extra walk by and stop, look at the camera and actors, and back up out of the shot. (Mentioned on the commentary). (00:24:30)

BillyBlake