Best mystery movie stupidity of 2000

Stupidity: For Sarah's murder to work, a lot of coincidences and unpredictable, convenient behaviour from the victim have to happen; she has to Miss the security guard and not hear them, she has to seek shelter of all places right in the costume room full of effigies of the killer, where the killer himself happens to be posing, she has to be completely inefficient at calling help with her cell phone.

Sammo ★

Stupidity: Phil and Rona are in their usual cabin for their usual get-together when Phil tries to tell Rona that Mona is dead, but Rona says, "You'll find me floating at the bottom of the Hudson." If you are floating in a body of water, you are on the top, not the bottom.

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