Revealing mistake: When Cindy and Buddy get trapped inside the cold chamber, she starts rubbing him to a point that it becomes masturbation. But when she's sitting on his legs doing the thing, in one side shot you can clearly see she is not holding his privates and her hand is just going up and down, closed but empty.
Continuity mistake: During the scene where Dwight is handing out the goggles, and right before the part where Brenda asks about the walkie-talkies, if you look behind Dwight, you will see that there is one more pair of goggles in the cabinet. After Brenda asks the question, the cabinet is empty.
Continuity mistake: At the end of the film, when Dwight gets pulled into the room and sits down in a chair beside Ray and Buddy, Ray's shirt is orange. Then when Dwight says, "I can't feel my legs," it cuts back, but Ray's shirt is yellow. It alternates throughout this scene between orange and yellow.