Robert Wise - Born To Kill (1947)

The day after her Reno divorce is finalized, Helen Brent plans to return home to San Francisco to the home of her foster sister, Georgia Staples, who inherited all the family money, and into the arms of her wealthy, upper crust fiance, Fred Grover. Two things that happen on that day of the divorce affect her return. First, she discovers two murdered dead bodies, about which she ultimately decides to do nothing in the negative consequences on her life if she does make a report. And second, she meets who she will eventually learn is Sam Wilde, whose slightly coarse around the edges exterior just adds to his masculine attractiveness, he who just happens to be heading to San Francisco himself on the same train as her. In their mutual attraction, he is able to infiltrate her life, regardless of his presence on her relationship with Fred. Eventually, there is indication that he is the murderer, which is indeed the case, the act all in a fit of jealousy in he taking decisive measure against anyone he feels makes him appear the fool. He, in turn, also correctly believes that he and Helen's attraction is in they being two peas in the same pod, where she is just as ruthless in wanting the world, the reason she still has Georgia, Fred and their money in her life. When Helen learns that a Reno private detective, Albert Arnett, has been hired to investigate the murders, she has to figure out how best to handle the situation to her and Sam's benefit. Thrown into the mix is Sam's best friend, Marty Waterman, the only person who truly understands Sam's disturbed mental state, and the only person who feels he can speak freely to Sam without impunity of a bullet from him.