Lady on a Train

Lady on a Train is a 1945 American comedic crime film directed by Charles David and starring Deanna Durbin, Ralph Bellamy, and David Bruce. Based on a story by Leslie Charteris, the film is about a woman who witnesses a murder in a nearby building from her train window. After she reports the murder to the police, who quickly dismiss her story, she turns to a popular mystery writer to help her solve the crime. The film received an Academy Award nomination for Best Sound.

Upon arrival, she slips away from Haskell and goes to the police, but the desk sergeant, seeing the novel in her hand, assumes she imagined the crime. She decides that Wayne Morgan must be able to solve a murder, finds him, and pesters him to get involved. Following Morgan and his fiancee into a theater, she sees a newsreel about the accidental death of shipping magnate Josiah Waringand recognizes him as the murder victim.Unable to find the crime scene, Nicki sneaks onto the grounds of Warings mansion. She is mistaken for Margo Martin, who was expected but has not come. Warings will is read by his lawyer, Wiggam Warings nephews Arnold and Jonathan are not surprised to receive a tokeninheritance, while the bulk of the estate goes to Margo Martinhis trophy fiancee, a singer at a nightclub he owns. Nicki snoops around the house and takes away a pair of bloody slippers that disprove the story of an accident. Two conspirators in the murder try but fail to stop her Saunders, who turns out to be the nightclubs manager and another heir, and the chauffeur Danny. ........

Source: Wikipedia