10 Most Disturbing Plot Twists In Non-Horror Movies

10. I Know Who You Are - The Machinist (2004)

The Machinist is best known for Christian Bale's insane dedication to the role of paranoid insomniac Trevor Reznik, and less remembered for its gripping plot and deliciously dark final twist.

After an accident at work attributed to his declining mental state and increasing paranoia, Trevor spends the film obsessed with tracking down Ivan (John Sharian), a co-worker everyone tells him doesn't actually exist. Even his moments of peace with waitress Marie (Aitana Sanchez-Gijon) aren't enough to save him from this madness.

With the mystery of Ivan and Trevor's past firing on all cylinders, the end of The Machinist reveals that Trevor has repressed his guilt over killing a young boy in a hit-and-run accident a year earlier, and that Marie, her son, and Ivan are all figments of his imagination, created to help him bury his guilt.

In the end, Trevor turns himself into the police, and for the first time since the accident lies down to get some well-needed rest, finally at peace with his conscience.