In Phantom Lady, Scott Henderson (played by Alan Curtis) goes out for a night on the town with a mysterious woman after his wife tells him she doesn't love him anymore. Scott and the unnamed lady have drinks at a bar, go out to a show where the songstress on stage wears the same elegant hat as Scott's guest, and then part ways outside of the bar. When Scott returns to his apartment, he finds detectives in the living room and his wife strangled to death in the bedroom. Because Scott's necktie is identified as the murder weapon, cops immediately zero on him as the main suspect. Scott must track down the mysterious lady who is his alibi, yet no one is cooperating. It is evident that witnesses who saw the two together at the bar and show have been bribed to keep their mouths shut. The only person who believes that Scott Henderson is innocent is his secretary Carol Richman, a woman clearly infatuated with her boss. When a jury convicts Scott of murder, Carol sets out to find the unknown woman and clear his name. Scott's best friend, Jack Marlow, arrives to help Carol. Franchot Tone plays Jack Marlow and doesn't enter the film until about 45 minutes in. Spoilers are coming after this set of screen captures, so if you don't want to know too much, beware!
If you enjoy 1940s film noirs, you'll want to check out Phantom Lady. It is available on DVD on Amazon and TCMShop.