The Ambassadors Theatre opened its doors on Thursday 5^th June 1913, just a year before the outbreak of The Great War, with the play Panthea. The original proprietors, The Ambassadors Theatre Ltd, employed Herbert Jay as managing director with the theatre commissioned by Richard Verney, 19^th Baron Willoughby de Broke. Theatre attendances had been spiralling downwards with many noting the need for a smaller theatre which could stage more intimate, modern plays and the Ambassadors fitted that need perfectly, seating well under 500.

The original décor was in the elegant style of Louis XVI, incorporating Parma violet, ivory and gold, with a horseshoe shaped single balcony only a few steps up from ground level and stalls built underground. The original plan had been to build two theatres simultaneously, but with the outbreak of war and the small matter of another building already occupying the neighbouring site, the Ambassadors sister theatre, the St Martin’s was not completed until 1916. This was highly relevant because an archaic law known as “Ancient Lights” meant that the Ambassadors had to be built lower than originally planned so as not to obscure light to the building on the site now occupied by the St Martin’s Theatre. The Ambassadors was built by Frank Rolison Littler and Herbert Jay with both theatres designed by the renowned theatre architect W G R Sprague.

Theatrical impresario Charles B Cochran recognised that the Ambassadors intimacy lent itself perfectly to theatrical revues and a series of miniature revues was performed here at the beginning of the First World War. After a performance of The White Headed Boy, the theatre became a piece of motion picture history, when, on Tuesday 18^th December 1920, the audience was invited to stay in their seats for about 30 minutes so they could be used as extras in The Adventures of Sherlock Holmes: A Scandal in Bohemia. Several scenes in the film occur in a West End theatre during the performance of a play and so the producers, Stoll Picture Productions Limited made West End and motion picture history by filming those scenes in the Ambassadors.

Thursday 3^rd November 1921 saw Ivor Novello make his London West End debut here in the ensemble of Sacha Guitry’s play Deburau and on Thursday 10^th September 1925, American actor Paul Robeson also made his West End debut here in the lead role in Eugene O’Neill’s The Emperor Jones.

The 1930s was no less significant – it was here in the Ambassadors that, on Wednesday 15^th May 1935 a young Vivien Leigh made her West End stage debut in Ashley Dukes’ comedy The Mask of Virtue. This was the play in which Laurence Oliver first saw her perform and so mesmerising was she, that just days later she signed a film contract worth £50,000 – around £3.5 million today.

You’ll find this “dainty little playhouse” on the edge of Covent Garden opposite the world famous Ivy restaurant. The Ivy, which opened in 1917 was then just a small Italian café  but quickly became renowned as a haunt for theatrical celebrities, so much so that in a 1940s revue at the Ambassadors called Sweet And Low, a satirical sketch was included entitled Poison Ivy with star of the show Hermione Gingold exchanging scandalous celebrity gossip with the audience.

On Tuesday 25^th November 1952 the world’s longest running play, The Mousetrap by Agatha Christie, opened at the Ambassadors with an original cast including Sir Richard Attenborough and Sheila Sim. On Friday 13^th September 1957, it became the longest running play in the West End with 1,998 performances ( a record previously held by Noël Coward’s Blithe Spirit) and on Saturday 12^th April 1958, it became the longest running production of any form in the West End with 2,239 performances (previous held by the musical Chu Chin Chow). It would stay for over two decades, until Saturday 23 March 1974 when it moved next door to the St Martin’s Theatre where it is still running. Prior to the Mousetrap’s move, in March 1973 the Ambassadors was granted Grade II listed status by English Heritage.

The 1980s saw notable productions including the play 84 Charing Cross Road, which ran for fourteen months and the Royal Shakespeare’s hit production of Les Liaisons Dangereuses which transferred here in October 1986 and stayed for almost four years.

In 1996, the venue was bought by its namesake the Ambassador Theatre Group, one of the largest theatre operators in the West End. The auditorium was divided into two smaller spaces by creating a false floor at circle level for use by the Royal Court which was undergoing refurbishment in Sloane Square. “The Stage Space” occupying the Stalls area and “The Circle Space” above staged the Royal Court’s “Theatre Upstairs” studio based work. The first production during this period was the world premiere of Harold Pinter’s Ashes to Ashes. The Royal Court’s main house productions were staged in the nearby Duke of York’s Theatre on St Martin’s Lane.

Following the departure of the Royal Court in April 1999, the auditorium transformed back into one space and was renamed the New Ambassadors. Along with the new name came a new ethos of hosting short runs of new work and transfers from fringe and regional theatres. However, within a few years, the theatre largely reverted to receiving more commercial material. Marie Jones’ award-winning comedy Stones In His Pockets opened here in May 2000, transferring a few months later to the Duke of York’s where it stayed for the next three years.

In the early 2000s, other noteworthy productions included Samuel Beckett’s Krapp’s Last Tape starring John Hurt, and Eve Ensler’s The Vagina Monologues which went on to great success, moving theatres several times and featuring a string of big name performers including Jerry Hall, Miriam Margolyes, Lisa Stansfield and Spice Girl Mel B.

In 2006, Channel 4 television and producer Sonia Friedman began a televised search called The Play’s The Thing for a new commission from a previously unknown writer to be staged in the heart of London’s West End. The Ambassadors was the natural choice of venue and from over 2000 entries, Kate Betts’ play On The Third Day was chosen. The play featured Paul Hilton, Maxine Peake and Tom McKay but despite the publicity around the TV show, the play closed after a run of just six weeks. Later the same year, the Ambassadors played host to the landmark revival of Sir Peter Hall’s production of Waiting for Godot.

On 4^th April 2007 it was announced that ATG had sold the venue to Sir Stephen Waley-Cohen, 2^nd Baronet and theatrical producer who renamed the venue The Ambassadors as it once was, and began an extensive programme of refurbishments.

On 4^th October 2007, after a successful five year run at the Vaudeville Theatre, the highly entertaining Stomp transferred here, remaining for over a decade until 7^th January 2018.

In May 2014 it was announced that Sir Cameron Mackintosh would be buying the theatre. At the time, Mackintosh said that he would be seeking permission to carry out major alterations, converting the building from a traditional proscenium arch theatre into a 450 seat thrust stage auditorium and to rename it the Sondheim Theatre  This was Sir Cameron’s second attempt at designing a studio theatre after failed plans to remodel the Queen’s theatre in 2003, although the Queen’s did eventually become The Sondheim.

For the next few years, the theatre remained in the hands of Sir Stephen Waley-Cohen and the sale did not proceed. For many, the decision felt like a reprieve for the theatre’s elegant auditorium which had been earmarked for destruction, albeit with plans to preserve parts of Sprague’s original designs within a new bar.

In December 2018, Waley-Cohen instead sold the theatre back to ATG for £12 million – double the price that Sir Cameron would have paid.