The Mousetrap

The Mousetrap is about a young couple, Mollie and Giles Ralston, who have opened a new hotel in the converted Monkswell Manor. They are snowed in together with four guests and an additional traveler who ran his car into a snowdrift. Detective Sergeant Trotter arrives on skis to inform the group he believes a murderer is on his way to the hotel following the death of Miss Maureen Lyon in London.

When one of the guests is discovered dead, they realize that the murderer is already there. The suspicion falls first on an erratic young man who fits the description of the supposed murderer. However, it quickly transpires that the killer could be any one of the guests or even the hosts themselves.