20. The Child Is Actually A Crazy, Adult Dwarf - Orphan
The Twist: Esther (Isabelle Fuhrman), the apparently 9-year-old girl adopted in the movie, is actually a 33-year-old woman whose dwarfism makes her look like a child. She uses make-up to better disguise herself as a child, and what's more, she's terrorised many previous families, always killing them when the father rejects her sexual advances.
Why It's Stupid: This one's pretty self-explanatory: how is anyone supposed to take a thriller movie seriously when it serves up a twist this utterly bonkers? Though it doesn't completely sink the movie because of the twist's perverse entertainment value, it does hurl credibility right out of the window (in an otherwise relatively grounded film) and results in more than a few unintentionally hilarious moments.
Is it stupid? Absolutely, but also relatively enjoyable thanks to Fuhrman's excellent, go-for-broke performance.
Stay at home dad who spends as much time teaching his kids the merits of Martin Scorsese as possible (against the missus' wishes).
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