Stupidity: When Jody traps Michael in his room, he does so by sticking a screwdriver between the the door and the jamb. This likely wouldn't accomplish much regardless, but it especially wouldn't work in this situation because the door opens into the room, so Michael could simply open the door and the screwdriver would fall on the ground.
Phantasm (1979)
1 stupidity
Directed by: Don Coscarelli
Starring: Reggie Bannister, A. Michael Baldwin, Bill Thornbury, Kathy Lester
Revealing mistake: When the maintenance man grabs mike and won't release him, you can tell Mike has a mouth full of blood that is used when he bites the man's arm.
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