O’Mara has been a television star since the 1960s with credits that The Saint and The Avengers.
She played The Rani in Doctor Who from 1985-86 and the ruthless businesswoman Laura Wilde in the BBC drama Howards’ Way. She also made an appearance on Absolutely Fabulous as Jackie Stone
Born in Leicester, UK, O’Mara was the daughter of actress Hazel Bainbridge (The Family Way) and John Carroll, who caught the attention of Hammer Studios which cast her in the 1970 films The Horror of Frankenstein and The Vampire Lovers.
She also founded The British Actor’s Theatre Company and wrote four books.