The Princess's Theatre or Princess Theatre was a theatre in Oxford Street, London. The building opened in 1828 as the "Queen's Bazaar" and housed a diorama by Clarkson Stanfield and David Roberts. It was converted into a theatre and opened in 1836 as the Princess's Theatre, named for then Princess Victoria before her accession as queen. After an unsuccessful series of promenade concerts, alterations were made on the interior, and the theatre was reopened on 26 December 1842 with Vincenzo Bellini's opera La sonnambula. The theatre, by now under the management of John Medex Maddox, presented operas and other entertainments, such as General Tom Thumb.