"The murderer is with us--on the train now . . ."

Just after midnight, the famous Orient Express is stopped in its tracks by a snowdrift. By morning, the millionaire Samuel Edward Ratchett lies dead in his compartment, stabbed a dozen times, his door locked from the inside. Without a shred of doubt, one of his fellow passengers is the murderer.

Isolated by the storm, detective Hercule Poirot must find the killer among a dozen of the dead man's enemies, before the murderer decides to strike again.