Christie's play began as a radio play titled Three Blind Mice. She had to give it a new title when she adapted it for the stage because there was already a play with that name. The new title, The Mousetrap, was inspired by Shakespeare's Hamlet, in which Hamlet calls his play within the play "The Mousetrap" because he hopes to use it to catch Claudius as his father's killer.

You can think of the characters in Christie's play as mice caught in a trap. They are all snowed in at a hotel and discover that one of them is a murderer when they find the dead body of one of the guests. The play revolves around figuring out who the killer is.