The Mermaid Theatre was a theatre encompassing the site of Puddle Dock and Curriers' Alley at Blackfriars in the City of London, and the most recently built in the City since the time of Shakespeare. It was, importantly, also one of the first new theatres to abandon the traditional stage layout; instead a single tier of seats surrounded the stage on three sides.
The 20th-century theatre was the life's work of actor Bernard Miles with his wife, Josephine Wilson. His original Mermaid Theatre was a large barn in his house in the St. John's Wood area of London. This seated 200 people, and during 1951-1952 it was used for concerts, plays and a celebrated opera production of Dido and Aeneas with Kirsten Flagstad, Maggie Teyte and Thomas Hemsley, conducted by Geraint Jones, which was recorded by HMV. For the third season in 1953, the Mermaid Theatre was moved to the Royal Exchange.