The play began as a radio drama called Three Blind Mice, written for Queen Mary's 80th birthday. Its first West End cast was led by Richard Attenborough and his wife, Sheila Sim. Christie expected a run of a few months. Instead it passed 30,000 performances in 2025, moving from the Ambassadors to the neighbouring St Martin's Theatre in 1974 and pausing only during the COVID-19 pandemic. Audiences are asked at the end not to reveal who the killer is.
In 1947 the BBC asked Christie to write a radio play for Queen Mary, who was a fan. The 30-minute Three Blind Mice drew on a real case, the death of a boy in foster care. Christie expanded it into a stage play, and because another play already had the title, her son-in-law suggested The Mousetrap, from the play-within-a-play in Hamlet.
The story is set in a snowbound guest house, where a group of strangers learn that a murderer is among them. After a tour, including a first performance in Nottingham in October 1952, it opened at the Ambassadors Theatre on November 25. Critics were polite, and Christie gave the rights to her grandson as a birthday present, telling friends she expected it to run perhaps eight months.
The play became an institution. By the time it moved next door to the St Martin's in 1974, it was already the longest-running play in British history. A tradition asks each audience to keep the ending secret, and the film rights were sold on the condition that no film be made until the West End run had ended at least six months earlier. It has never ended long enough for a film.
Key people: Agatha Christie, Richard Attenborough, Sheila Sim