Continuity mistake: Views of Michelle's car wreck were inconsistent. When the car veered to the right and was headed toward the tree, the driver's view showed most of the car was to the left of the tree trunk. On impact, it looked like the right side headlight hit the middle of the tree trunk. Michelle got out and a rear view showed the tree trunk roughly lined up with the steering wheel (i.e, more than half of the car was to the right of the trunk). After impact, both headlights were shining in front of the tree.
Continuity mistake: James lit the cigarette he gave Amanda, and she was shown taking one puff. Amanda tells part of the Empty Man story and the ashes on the tip of her cigarette are the same when she takes a second puff. After continuing the story for about two minutes, the length of the ashes still have not increased when Amanda is about to take the third puff. (00:37:21 - 00:39:53)
Continuity mistake: After Wes was clobbered and on the floor, he had a long stream of water/mucus coming out of his nose or mouth and his lips were wet when he was standing up, but his lips/mouth/nose were totally dry when the killer put his gloved hand over Wes' right shoulder. (00:33:40)