9 Most Undeserved Movie Plot Twists

M. Night Shyamalan doesn't make exclusively bad films - The Sixth Sense earned its ghostly reveal and Unbreakable is an original take on superheroism - but the director often throws in twists that come at the expense of his movies.

Anti-climactic alien invasion thriller Signs is a good example. After building up a sense of creeping horror as the extraterrestrials closed in on Graham (Mel Gibson), his brother Merrill (Joaquin Phoenix) and his children (Rory Culkin and Abigail Breslin), the movie dropped a clanger by revealing that water is like Kryptonite to the aliens.

This simply doesn't work as a twist because it means the invaders should have keeled over in agony the moment they set foot on our planet, given how much water vapour is in its atmosphere. Moreover, why would a race advanced enough to traverse the galaxy choose to land on a planet that's 70% covered in the one thing that kills them?