Continuity mistake: The little girl who was missing after falling off the cliff, suddenly shows up again after the evil woman is struck by lightning and is seen standing with the other children to react. But then she's gone again only to then show up with Santa.
Character mistake: Cynthia Kellogg comes forward to voluntarily give information about the James Urbanski case. Detective Nealy tells Kellogg, "As a matter of procedure, I have to inform you of your rights." Kellogg says she didn't do anything so doesn't need a lawyer. Nealy replies, "This is your right" and proceeds to inform her of her Miranda Rights. Miranda warnings are applicable to suspects/defendants who are in police custody (under arrest) and about to be interrogated, not voluntary witnesses. (00:03:02 - 00:03:57)
Other mistake: Jack gets hit in the face by a car trunk but when he wakes up later there's no cuts or bruises on him.
Visible crew/equipment: When Liz walks into the art studio early in the morning, in the shot where she opens the door and enters, a boom mic can be seen in the bottom left hand corner of the frame and is quickly pulled out of shot. (03:14:54)
Revealing mistake: When the alligator breaks the wall after David failed to kill him with the grenade, the fake jaws are strikingly obvious and completely different from the alligator's look in the part that follows. (00:49:45)
Other mistake: The sword champion is murdered in a dark room. Cut to Tarek Richards by his corpse. The room is still shrouded in darkness, which makes for a cool transition. However, when the camera pans out and someone (with an audible click) turns on the lights, you realise that the room is full of cops which up to that moment have been working in a dark room for no reason - and they have been doing things that require reading and writing, like collecting witness statements.
Character mistake: In the very first scene, in the first shot you see a sign in Spanish that says "NO PASE por orden del departamento de arquiologia". The correct Spanish word is arqueologia.