Murder in the Private Car is a 1934 American pre-Code mystery romance film starring Mary Carlisle, Charles Ruggles and Una Merkel.

She learns from lawyer Alden Murray (Porter Hall) that she is actually the daughter of railroad tycoon Luke Carson (Berton Churchill).

Once it is found out that she is an heiress, there is an attempt on her life by her bodyguard and chauffeur, which is foiled by Godfrey Scott (Charles Ruggles).

A telegram from her father is intercepted and replaced, telling her to meet him in New York instead of Los Angeles, and that a private train car has been arranged.

In the private car, the lights go out and an announcement is heard, "Eight hours to live", after which Scott introduces himself to Ruth and her friends as a sleuth who prevents crime.

Now with no reason to go to Los Angeles, her father joins Ruth's party in the private car, dismissing the danger, refusing to believe George when he says that Murray was stabbed through the eye.

Carson found Elwood's control center, and now he opens the shutters and uses a radio transmitter to broadcast a warning of the imminent collision and explosion.