A somewhat daffy book editor on a rail trip from Los Angeles to Chicago thinks that he sees a murdered man thrown from the train. When he can find no one who will believe him, he starts doing some investigating of his own. But all that accomplishes is to get the killer after him.
A man and a woman, each with a stable marriage of their own, meet in the wagon compartment. The short encounter of two strangers causes restlessness within their personal views about the world, implying possible romance. Once the train reaches its destination, they go apart without a single word spoken, and return to their world of security.
Suspicious husband follows his wife and her male boss on their business trip.