Too Late for Tears (1949)

One night on a lonely highway, a man in a speeding car tosses a satchel of money meant for somebody else into Jane and Alan Palmer's convertible as they are heading down a mountain road to a party. When they open the satchel and see what's inside, Alan wants to turn it over to the police, but Jane, with a life of luxury now within reach, persuades him to hang onto it "for a while." Soon afterward, the Palmers are tracked down by one Danny Fuller, a sleazy character who claims the money is his. To hang on to the cash, Jane will need to exercise all her feminine wiles, even if it leads her to dangerous circumstances and criminal behavior.