Sheila Hancock was born in Blackgang on the Isle of Wight, the daughter of Ivy Louise (n?e Woodward) and Enrico Cameron Hancock, who was a publican. Her sister Billie is seven years older (and worked as a variety artist until retiring to Antibes in 2003 at the age of 79). After wartime evacuation, Hancock attended Dartford County Grammar School and the Royal Academy of Dramatic Art.

She worked in repertory during the 1950s and made her West End debut in 1958, replacing Joan Sims in the play Breath of Spring. She then appeared in Joan Littlewood's Theatre Workshop production of Make Me An Offer in 1959, and her other early West End appearances included the revue One Over the Eight with Kenneth Williams in 1961 and starring in Rattle of a Simple Man in 1962.

In 1965 she made her Broadway debut in Entertaining Mr Sloane. In 1978 she played Miss Hannigan in the original London cast of the musical Annie and two years later she played Mrs Lovett in the original London production of the musical Sweeney Todd.

She appeared in The Winter's Tale, Titus Andronicus and A Delicate Balance for the Royal Shakespeare Company. At the National Theatre she appeared in The Cherry Orchard and The Duchess of Malfi. She also directed A Midsummer Night's Dream for the RSC on tour and was the first female director at the National, with The Critic.

In 2006 she played the role of Fraulein Schneider in the West End revival of the musical Cabaret at the Lyric Theatre. For this role she won the Laurence Olivier Award for Best Performance in a Supporting Role In A Musical. In 2009 she began playing Mother Superior in Sister Act the Musical at the London Palladium, for which she was nominated for a Laurence Olivier Award (2010).

Sheila Hancock was born in Blackgang, Isle of Wight on 22 February 1933.