Revealing mistake: When the doctor is cutting the forehead, a red tube to release fake blood can be seen behind the scalpel. (00:30:12)
Revealing mistake: When the doctor probes the brain to move the leg up, a hand holding an object can be seen at the crotch, which is used to fake an erection next. (00:31:46)
Revealing mistake: When the doctor is stapling the head, the staples are pre-attached. Also, he stops midway in the close-up shot. (00:37:38)
Revealing mistake: The wire, which will be used to lift Billy when the T-Rex is supposedly lifting him by the head, is visible. (00:48:18)
