For the last 40 years, there's only been one reason to go to the St Martin's Theatre: it's the home of the world's longest continuously running play, Agatha Christie's The Mousetrap, which transferred to the theatre in 1974 from the Ambassadors just down the street where it had been running since 1952. The Mousetrap is a murder mystery with a notorious twist ending -- theatregoers are implored not to reveal it, which doesn't mean it hasn't escaped into the public domain -- and although the entire set has been changed twice, one prop remains from the original production, and a radio broadcast still features the voice of an actor from the original cast. The nearest Tube station is Leicester Square, Charing Cross railway station is ten minutes' walk away, and the theatre is served by the 14, 19, 22, 24, 29, 38, 40 and 176 bus routes. There are car parks on Upper St Martin's Lane and Bedfordbury, and street parking is allowed on single yellow lines after 6.30pm and on weekends.