The Mousetrap

The Mousetrap is a murder mystery play by Agatha Christie. The longest-running West End show, it also has by far the longest run of any play in the world, reaching its 30,000th performance on 19 March 2025. The play opened in London's West End in 1952 and ran continuously until 16 March 2020, when the stage performances had to be temporarily discontinued during the COVID-19 pandemic. It then re-opened on 17 May 2021. As of 2022 the play had been seen by 10 million people in London.

A whodunit, the play has a twist ending which the audience are traditionally asked not to reveal after leaving the theatre. There are eight members of the cast, and by 2012 more than 400 actors had played the roles. Richard Attenborough was the original Detective Sergeant Trotter, and his wife, Sheila Sim, the first Mollie Ralston – owner of Monkswell Manor guesthouse. Since then few of the cast have been headliners, with Stephen Moss in The Guardian writing that "the play and its author are the stars".