This is one of my favorite movies, with a great script by Billy Wilder and Raymond Chandler, based on a novel by James M. Cain.
But there's one brief bit of dialogue that always struck me as silly, for some reason:
Walter: I'm crazy about you, Baby.
Phyllis: I'm crazy about you. Walter.
Walter: The perfume you're wearing - what's the name of it?
Phyllis: I don't know. I got it in Ensenada.