10 Greatest Murder-Mystery Films That Fooled Us All

3. Shutter Island

Two U.S. Marshals arrive at Shutter Island to investigate the disappearance of a patient at Ashecliff hospital for the criminally insane. What starts out as a calm, logical, and composed narrative turns into a compelling psychological thriller that follows the protagonist, Teddy, into the depths of his own mind.

Teddy, at first, starts having migraine headaches, then begins having disturbing dreams of his dead wife who causes Teddy to question the motives of the staff, patients, and even his own partner. The reveal occurring at the top of the lighthouse all but makes us question our own reality and who we really are.

The final scene is leaves the audience speechless as Teddy says, "Which would be worse? To live as a monster or die as a good man?"