Born in Canada in 1927, she was the daughter of a chef from Barbados who worked on the Canadian Pacific Railway. Lucas acted in amateur productions as a teenager in Toronto before moving to London in 1954 to train as a singer. The following year, she made her West End stage debut in the revue The Jazz Train at the Piccadilly Theatre, a production that also gave Bertice Reading one of her early successes.
Lucas went on to carve out a distinguished musicals career that included appearances alongside Elisabeth Welch and Millicent Martin in The Crooked Mile (1959), and as Barbra Streisand's maid, Emma, in Funny Girl and Mammy in Harold Fielding's acclaimed production of Gone With the Wind (1972). Her last stage musical role was alongside the vaudeville star Jack Gilford in Look to the Rainbow (1985), but the actress's other West End roles included appearances in the straight play The Genius and the Goddess (adapted from an Aldous Huxley novel, 1962) and the Neil Simon comedy The Sunshine Boys (1975).
Other landmarks in Lucas's stage career included playing the first black Martha in Edward Albee's Who's Afraid of Virginia Woolf? at the Connaught Theatre, Worthing, and her first appearance with Norman Beaton, in the musical Bakerloo to Paradise (1969), which failed to make an impact and did not reach the West End. With the National Theatre, she acted in George Bernard Shaw's Back to Methuselah (alongside Derek Jacobi, 1969) and the world premiere of The National Health (1969), both at the Old Vic, as well as Cyrano (Cambridge Theatre, 1970) and Tyger (New Theatre, 1971, with Norman Beaton and Maureen Lipman).
When she was cast as the Leader of the Bacchantes in the National Theatre production of The Bacchae, Lucas objected to Sir Peter Hall's insistence that all the female characters should appear nude and won a partial victory by taking to the stage carefully draped. She also acted Florrie in Trinidad Sisters (Donmar Warehouse, 1988), Mustapha Matura's black version of Chekhov's The Three Sisters, and the Nurse in Dame Judi Dench's production of Romeo and Juliet (Open Air Theatre, Regent's Park, 1993), her final stage performance.
Her few feature films included Miracle in Soho (starring John Gregson, 1957) and Outland (alongside Sean Connery, 1981), but it was as Pearl Foster in two series of The Fosters (1976-77) on television that Lucas gained screen popularity. She and the celebrated black actor Norman Beaton, as her husband Samuel, played the parents of a South London immigrant family. Among those playing their three children were the comedian Lenny Henry and the actress Sharon Rosita.
Lucas also played "bald, black, lesbian mother" Velma in the sitcom Agony (1979); Pearl, one of the staff at Ashvale Advertising, in two series of My Husband and I (1987-88); Gertrude in the children's series Bluebirds, starring Barbara Windsor; two characters in EastEnders - a district nurse 1985, and nine years later Alice Alexander, who found it difficult to come to terms with her daughter Della's revelation that she was gay - and an old flame of the Peckham barber Desmond in the Channel 4 sitcom Desmond's (reuniting her with Norman Beaton). She also made appearances in the television film A Caribbean Mystery (1983) and the mini-series Ellis Island (1984).
Isabelle Harriet Lucas, actress: born Toronto, Canada 3 December 1927; married 1957 Maurice Jennings; died Kingston- upon-Thames, Surrey 24 February 1997.