The Secret In Their Eyes
This movie bagged the Academy Award for Best Foreign Language Film. If there was a category for Best Plot Twist, we are sure that The Secret In Their Eyes would have won that as well. Morales does not only know the killer, but he has actually locked up the guy in a cell in the countryside for decades.
Reservoir Dogs
In the debut film of filmmaker Quentin Tarantino, we are treated to a reversal of a famous trope. It turns out that one of the bad guys is on the side of good! Mr. Orange is actually an undercover cop. Mr. White, who killed two other guys in his defense, is shocked to hear this but kills the traitor anyway.