The Playhouse Theatre is a West End theatre in the City of Westminster, located in Northumberland Avenue, near Trafalgar Square. The Theatre was built by F. H. Fowler and Hill with a seating capacity of 1,200. It was rebuilt in 1907 and still retains its original substage machinery. As of November 2021, the theatre has been refurbished and renamed as the Kit Kat Club, home to a new revival of the musical Cabaret with a seating capacity of 550. Set in 1929–1930 Berlin during the twilight of the Jazz Age as the Nazis are ascending to power, the musical focuses on the hedonistic nightlife at the seedy Kit Kat Klub and revolves around American writer Clifford Bradshaw's relations with English cabaret performer Sally Bowles.

The theatre was restored to its 1907 design by impresario Robin Gonshaw, opening again in October 1987 with the musical Girlfriends. A commercial building, Aria House, was erected above the theatre. In 1988, novelist and politician Jeffrey Archer bought the Playhouse for just over £1 million. The following year, the theatre was offered commercial sponsorship by a financial services' company, and for a while it was known as the MI Group Playhouse. In 1991, the Playhouse became home to the Peter Hall Company, and a number of critically and commercially successful plays were performed there, including Tennessee Williams' The Rose Tattoo (1991), starring Julie Walters and Moliere's Tartuffe (1991), starring Paul Eddington and Felicity Kendal. Around this time the basement bar area of the theatre was converted into a private restaurant, Shaws, but the enterprise was unsuccessful and the space was later converted back into a bar/cafe. In 1992, Archer sold the Playhouse to the writer and impresario Ray Cooney for just over £2 million. That year Cooney staged the West End premiere of his latest farce It Runs in the Family at the Playhouse. This was followed by Jane Eyre (1993), adapted by Fay Weldon and starring Tim Pigott-Smith; Frederick Lonsdale's On Approval, (1994), starring Simon Ward, Martin Jarvis and Anna Carteret; and Ray Cooney's Funny Money in 1995. In 1996, Cooney sold the Playhouse to American investment banker Patrick Sulaiman Cole, whose first production was a critically acclaimed revival of Henrik Ibsen's A Doll's House in 1996, directed by Anthony Page and starring Janet McTeer. Later that year, the theatre was closed for complete refurbishment under the direction of English Heritage, with the auditorium luxuriously decorated, with grandiose murals, caryatids, golden pillars, carved balustrades, and shining gold decoration. It reopened in 1997 with Sulaiman Cole's production and the West End première of Anton Chekhov's The Wood Demon. This was followed by Sulaiman Cole's production of a first ever West End Snoo Wilson premiere, "HRH", directed by Simon Callow, about the British Royal Family's Duke and Duchess of Windsor, which opened the day after the death of Diana, Princess of Wales. The play was harshly reviewed as anti-Royal. The theatre returned to life as a commercial receiving house with several seasons of Almeida Theatre and Cheek by Jowl productions, including the popular but critically panned premiere of David Hare's The Judas Kiss.