Grade II* listed building.The Theatre Royal opened in 1787 at a cost of £4,000 and comprised an auditorium and stage housing contained within a simple rectangular brick building. Flanking this on the south side was the original, so-called 'Royal House' (manager's house). The paybox and entrance foyer formed a single-storey adjunct to the Addington Street frontage. The structure of the 1787 building partly remains, but in 1874 the theatre was remodelled by Jethro Thomas Robinson (designer of the 'Old Vic' and father-in-law to Frank Matcham). Robinson removed the old auditorium and stage, increasing the width by demolishing one side wall, and doing odd things with the old roof trusses in order to extend their span. In so doing the depth of the Royal House was halved and reduced to little more than a facade. Robinson also rebuilt the front-of-house areas and frontage. This is in stucco of two storeys and four bays, defined by fluted pilaster strips topped by a cornice and parapet. The two bays to the right curve round into the side street, with the entrance in the corner bay. Robinson's auditorium is a smaller version of his 'Old Vic' having two horseshoe balconies supported by iron columns along the line of their fronts. The balconies curve round the sides to meet the elliptically arched proscenium which rises directly to the underside of the saucer-dome ceiling. When a new scene dock was constructed to the rear in 1994 the floorings of the 1878 rear wall were revealed to be well above the present, suggesting that the earlier theatre had no significant stage basement. In 1841, the Royal was used as a chapel and between 1930 and 1934 it was in use as a cinema.