Mysterious Crossing (1936)

"OLD MAN RIVER GIVES UP HIS SECRETS to a reporter with a nose for news and an eye for a pretty girl!"

While crossing on the train ferry to New Orleans, roving reporter Addison Francis Murphy borrows money from singing hillbilly "Carolina," then loses it all in a crap game. Outside on deck, Murphy sees two men shaking hands, and after he looks away, hears a splash of water and discovers both men have disappeared...