Opened : 23rd November 1916
Arcihtect : W G R Sprague
Seats : 550

Designed as a companion at the adjacent Ambassadors Theatre, these two theatres are actually very different. In contrast to the fancy plasterwork seen in the Ambassadors Theatre auditorium, the St Martins Theatre has a polished wood interior - unique in the West End. The theatre was renovated in 1961.

Productions here include the premiere production of the popular JB Priestly play When We Are Married in 1938. In 1945 Edward Percy's murder tale The Shop At Sly Corner enjoyed a run of 863 performances. More recently Anthony Shaffer's thriller Sleuth had a run of 3 years starting in 1970. The theatre is best known for it's current production of Agatha Christie's The Mousetrap which originally opened at the Ambassadors Theatre on 25 November 1952 before transferring to the St Martins Theatre on 25 March 1974.