Agatha Christie's play with the longest initial run is The Mousetrap. It opened in London's West End in 1952 and became the longest-running play in the world.
The production began at the Ambassadors Theatre on 25 November 1952 after a provincial tour. In 1974, it moved next door to St Martin's Theatre, transferring without a break in its initial run. This continuity helped preserve its record-setting status.
The play began as a radio drama called Three Blind Mice, broadcast in 1947 as a birthday gift for Queen Mary. Christie later adapted the idea for the stage. Its tightly constructed murder mystery takes place at Monkswell Manor guesthouse, where a group of stranded visitors becomes trapped with a killer.
The Mousetrap is also famous for its surprise ending. Audiences are traditionally asked not to reveal the solution after the performance. The production passed 30,000 performances in 2025, although performances were temporarily interrupted by the COVID-19 pandemic.