Gray appeared in many television programmes, her first appearance being in Love in Waiting in 1948. She had several roles in the 1970s including parts in Fawlty Towers, as the pediatrician wife of a Psychiatrist baffled by Basil's behaviour, The Crezz, Catweazle, and in the 1980s with Doctor Who story Arc of Infinity and the World War Two drama Tenko. She appeared as the Queen in the BBC sitcom The Black Adder (1983), with Rowan Atkinson as her son in the title role, and as Mrs. Palmer in Solo (1981–82), another comedy, this time with Felicity Kendal in the lead as her daughter.

In 1949 Gray married actor and later Mencap chairman and President Brian Rix, who became a life peer in 1992. They had four children--two sons and two daughters. Their eldest child, daughter Shelley (born 1951), had Down syndrome and died in July 2005, aged 53.

Their other daughter Louisa (born 1955) is an Actress. Their eldest son Jamie (born 1959) is a children's author who has produced television programmes such as My Hero. They had one other son, Jonathan (born 1960).

She remained active until the late 1990s, appearing in Agatha Christie's Poirot, the films The Girl in a Swing (1988) and Four Weddings and a Funeral (1994), and as Hilary in the British television comedy Dinnerladies.

Gray died in hospital on 18 February 2013, aged 83.