The Killing (1956)

Directed by Stanley Kubrick

Quintessential yet often overlooked is this early Stanley Kubrick classic.  It's a heist film that starts slow but accelerates quickly as the plan goes into action culminating in an unforgettable conclusion.  Often classified as film noir because the story is told from the criminal's POV and they are characters with reasons for their actions, not just flatly rendered bad men. However it doesn't have the necessary dark tonal quality that would make it a true noir in my opinion. Kubrick is sardonic, not dark.