Plot hole: No matter how hard they tried, there's no way Pendleton could have covered up a killing spree like Brenda's. One of the 6 families who lost children would have said something to the media, if not Reese herself.

Continuity: When they are filming, the main girl says they're finished and when the lesbian girls asks her what's wrong, she has documents in her hand. In the next shot they're gone, then in the next shot they're back again.

Continuity: In the scene in the mine, when the killer attacks the black guy, his miner's light is knocked off. A few seconds later when it switches back to him, he's wearing it again.

Continuity: When Trevor is showing Amy the search he entered into the computer, Vanessa and Toby are both on the list. Why was Vanessa on it when she hadn't been attacked yet, and why was Toby on it when he hadn't been attacked at all?

Continuity: When the film crew are making their movie in the tunnel, the short white guy is standing on some platform for a minute, and you can clearly see a member of the film crew in the background. Then they disappear.

Plot hole: The black guy who is murdered in the Tunnel of Death is hit in the head with a pickaxe. The coroner should have discovered the wound from this, which would have sparked a proper investigation into the deaths, which may have led to the killer being caught earlier.

Factual error: When the girl with no kidney is decapitated, there's not nearly enough glass left in the window to take her head clean off while leaving it in the fixture.

Revealing: Trevor Stark appears as the twin brother of Travis. They both have the same scar on their left cheek. Therefore they are the same person and not twins.

Plot hole: When the professor put Travis' credits on the film he left in place of the real thing, some of the differences between film and credits would be very noticeable. For example, Sandra would be listed as having acted in the film, when she obviously wouldn't have been in the new film.

Continuity: Considering how carefully the killer cleaned the scene of Sandra's death, how likely is it that he would have left a cigarette at the scene of Simon's death? He didn't know that Amy was on her way out, so he wouldn't have rushed away from the scene.

Visible crew/equipment: During the scene in the Professor's office, there is a pan of the campus through the window. The reflection of a crew member can be seen briefly in the glass, wearing a gold watch and moving something.

Audio problem: In the final scene, when the guy is shot by Reece Wilson, you hear her shoot 4 times. But you can see at least 5 wounds.