Jason X (2001) - 6 major mistakes

Plot hole: When the film opens, Jason is bound and restrained in an empty room. After killing the six security guards and appearing in the hallway, he chases after Rowan with a machete. Where'd he get this? All the guards had guns, and the rest of the room was completely barren. [Apparently, there was a cut scene (unfortunately deleted scenes weren't included on the DVD) showing Rowan with a box of Crystal Lake newspaper clippings and other Jason material/evidence, and his machete was one of the items in the box. Still a mistake due to the empty room (ropey editing), but that's the reason.]

Revealing: When Kay-Em kicks Jason in the face during the fight sequence, you can see Kane's goatee.

Continuity: After Kay-Em blasts Jason's leg off, in following shots the position of the leg differs.

Revealing: When all of Rowan's clothes are removed from her frozen body, the outline of a strapless bra can be seen under the metal blanket. It is also seen later when she sits up and the metal blanket slips a little bit.

Factual error: When Jason is outside the ship and punches the hole to get back inside, the crew rushes to the door and close it because the lack of pressure is causing them to be sucked out of the ship. They go through several rooms and close multiple doors. Yet when Jason rips through the final door, there's no sudden rush of air, no loss of cabin pressure, even though there would be a continuous path to the broken outer wall of the ship.

Continuity: When the android steps up to fight Jason the first time, he throws his machete at her and hits her square in the chest. For the rest of the movie there is no hole in her jumpsuit.