• April 22, 1955 – 1,000th performance.
  • September 13, 1957 – Longest-ever sun of a “straight” play in the West End.
  • April 12, 1958 – Longest-ever run of a show in the West End with 2239 performances (Previous holder was Chu Chin Chow).
  • December 9, 1964 – 5,000th performance.
  • December 17, 1976 – 10,000th performance.
  • December 16, 2000 – 20,000th performance.

In May 2001 (during the London production’s 49th year, and to mark the 25th anniversary of Christie’s death) the cast gave a semi-staged Sunday performance at the Palace Theatre, Westcliff on Sea as a guest contribution to the Agatha Christie Theatre Festival 2001, a 12-week history-making cycle of all of Agatha Christie’s plays presented by Roy Marsden’s New Palace Theatre Company.A staging at the Toronto Truck Theatre in Toronto, Ontario, that opened on 19 August 1977 became Canada’s longest running show, before finally closing on 18 January 2004 after a run of twenty-six years and over 9,000 performances.Source: http://en.wikipedia.org/wiki/The_Mousetrap