Directed by Louis Malle
Written by Roger Nimier and Louis Malle
IMDB

Julien Tavernier murders his boss and makes it look like a suicide. He is in love with his boss' wife, and she's in on it. Foolishly, he leaves behind his grappling hook. On his way up to get it, the power to the building is shut off leaving him trapped in the elevator. His car, still running from before he saw the grappling hook, is stolen by a couple of youngsters, who then murder a couple at a hotel while trying to steal their car.
Suspenseful and a cool jazz soundtrack. What more could you ask for? This is a very cool movie, period. From the description on Netflix, I was expecting two people stuck on an elevator contemplating their inevitable arrest, but this is probably better than that movie would have been. It would make a good play, though.

9/10