Sally Dexter will join the cast of Sister Act as Mother Superior when Whoopi Goldberg leaves the production at the end of her limited season on 31 August 2010.

Dexter, whose previous West End credits include Billy Elliot and Bad Girls, will take over the role for the remainder of the musical's West End run, which producers have said must end on 30 October 2010, in advance of its Broadway debut in 2011.

The Mother Superior habit had previously been worn by Sheila Hancock, who left the production at the end of an extended contract. In the 1992 film on which the musical is based, Mother Superior was played by Maggie Smith. The limited period of just 23 performances which Whoopi Goldberg is spending in the role have seen an indifferent critical response but a notable box office boost for the show, which has run at the Palladium since May 2009.

The production was originally scheduled to close on 1 January 2011, making way for Andrew Lloyd Webber's revival of The Wizard of Oz however in May producers brought the date forward to 30 October and announced the production was looking for a new London home; no further announcements have been made. The Wizard of Oz will open at the London Palladium on 1 March 2011 (previews from 7 February).