Revealing mistake: When Jake is being tied up, he's holding his hands up to make it easier for the cannibal to tie up. Also when they drag him out of view, he's holding his head up so it doesn't drag the ground, although he's supposed to be unconscious during all this.
Revealing mistake: When the zombies are eating the intern in the hospital, you can see one of his ribs move as if it were made out of rubber. (00:51:20)
Revealing mistake: Sean Patrick Flanery plays a nerd who has trapped a female vampire in a cage. About 3/4 of the way into the movie, he tricks a co-worker into visiting, planning to feed him to her. He extends his right arm through the bars, and she starts to caress and kiss it, then begins to bite it and suck his blood. When he tries to withdraw, she tears off his arm at the shoulder. But in the next shot, he and Flannery both hit the floor outside the cage, and the co-worker's right arm is visible. However, when the scene begins, both Flanery and the co-worker are wearing watches on their left wrists, and in the shot of them on the floor, both have watches on the right, suggesting that the image has been reversed.
Revealing mistake: When Cris drives his car over the railroad crossing, the CGI locomotive which passes subsequently lacks a fuel tank which is usually between the two sets of wheels.
Revealing mistake: When Billy is looking at Nick's driver's license, for sex it says F for female.
Revealing mistake: At 39:55, actress Jaime King gets out of the shower, and she has just reached for her robe, and then on the bottom right corner of your screen you can see a bit of the flesh-colored body suit she's wearing. Continue to 40:00 where you see it again. Continue to 40:05-40:09 where you can see it, without slowing or stopping frame. (00:39:55)
Revealing mistake: After "Do you want to die with dignity" all hitmen drop their magazines of blanks.
Revealing mistake: When Joseph goes to pick up the prisoner, there's a close-up of the paperwork; the prop is something recycled, or perhaps a real prison movement slip with Alex Veadov's picture stapled on, because the character's name is Vadim Nezhinski, a white Russian, but the documents say "Anderson, Robert", with a B (Black) for race. (01:09:45)
Revealing mistake: During Ian's double-kill moment in the morgue, you can see the prosthetics on his chest crease once he drops to his knees for the fatal blows. (01:14:00)