Revealing mistake: When the cops raid Hoyt's apartment building, Billy the dog is barking at them. But when multiple cops reach his level, Billy whimpers and takes off up the stairs scared. However, you can see the dog's tail is still up and partly wagging. A scared dog's tail would be tucked between its legs, even when climbing stairs. (00:50:35)
Revealing mistake: After Hoyt is shot by the cops, Will escapes through a window. One cop fires an M16 at him and Will tries to go over some rails, which just break and he falls on garbage. In one shot where he lands, you can see the face of Nicolas Cage's stunt double. (00:51:40)