This is pure noir.
Lizabeth Scott and Arthur Kennedy are a couple who receive a satchel full of money that was intended for someone else (Dan Duryea). He wants to turn the cash over to the authorities; she wants to keep it---no matter what the consequences:
"Jane, Jane, what's happening to us---what's happening. The money sits down there in an old leather bag and yet it's tearing us apart. It's poison, Jane. It's changing you, it's changing both of us."
"Chances like this are never offered twice. This is it. I've been waiting for it---dreaming of it all my life, even when I was a kid."