Though the actor Dinah Sheridan, who has died aged 92, was an "English rose" of the type still firmly in vogue in British theatre and films of the immediate postwar era, she had a vivacity and depth of talent that went further than the label suggested.
The 1953 film that would almost certainly have turned her into an international star – but for an ill-judged second marriage to the head of the company that made it – was Genevieve. Two rival couples taking part in the London to Brighton veteran car rally were the backbone of the film, and Kenneth More as the brasher of the two male drivers and Kay Kendall as his glamorous model girlfriend had the more extrovert roles. But Sheridan was quietly appealing as the woman who would rather stand by the man prepared to lose the race (John Gregson) than win it with a less scrupulous fellow who might have been prepared to hurt an elderly car buff's feelings by driving off in the middle of their conversation.
Sheridan specialised in decorous English heroines, giving moderately prim performances in an era when being "ladylike" was considered desirable rather than off-putting. The fact that she was tall rather than the archetypal Little Woman was always concealed by skilful camerawork.
After a period appearing in reliable British films such as the royal command performance film Where No Vultures Fly (1951), about the adventures of an east African game warden, Genevieve was about to make her an international hot property. This would have enabled her easily to provide for herself and her two children.
However, in 1954 she married Sir John Davis, head of the Rank Organisation, who wanted her to give up her career and be a mother to his three children. In the eyes of his critics in the British film industry, Davis's oppressive personality helped strangle the industry at a time when it could have done with powerful friends. Her status as his wife had a critical affect on Sheridan's career and health.
She had been divorced from the actor Jimmy Hanley, a man of great charm whom she had first met in 1942 on the set of the film Salute John Citizen, in which she played the nurse who marries the eldest son of the house against some opposition. Sheridan admitted later that she had not known Davis well enough before marrying him. Soon she found that although he had told her about his first and third wives, he had not mentioned wives two and four.
She had a breakdown and wanted to stay in a psychiatric clinic, though was told she did not need psychiatric help. Instead she was baptised at the age of 41, and sought divorce on the grounds of cruelty.
Her career was revived when she appeared in a role virtually tailor-made for her: the ever-understanding mother in the 1970 film of the literary classic The Railway Children. Television work followed, notably in the comedy series Don't Wait Up (1983-90), with Tony Britton and Nigel Havers, and the motor-rallying drama The Winning Streak (1985). Her final TV role came in an episode of Jonathan Creek (1999).
Born in Hampstead Garden Suburb, north London, the "English rose" came from a thoroughly cosmopolitan background. Her parents – joint photographers by appointment to the Queen and Queen Elizabeth the Queen Mother – were Lisa Everth, a German, and Fernand Archer Mec, a Russian, so her birthname was Dinah Nadyejda Mec.
Her temperament was so bubbly that a French friend called her Mousse, after the foam given off by champagne: when she had both knees replaced in her 1970s, she said the crutches made her feel like "a pissed spider". But the prospect of taking to the stage with a name pronounced "mess" held no appeal, and she chose Sheridan from a telephone directory.
After Sherrards school in Welwyn Garden City, Hertfordshire, she studied at the Italia Conti stage school, and her first professional job was as an understudy in Where the Rainbow Ends in 1932. She appeared in Peter Pan as Wendy two years later, and then in 1936 as Peter.
Most of the plays she was cast in subsequently were the comfortably middle-class fodder of the period, but from the late 1930s she found a place in British films, including the role of the glamorous Steve, the female foil in the cult detective film Calling Paul Temple (1948).
Sheridan's daughter Jenny also became an actor, and presented the ITV children's series Magpie, while her son Jeremy became a Conservative MP. They survive her; a second daughter with Hanley died after three days.
Sheridan's third marriage, in 1986, was to the actor John Merivale, who died in 1990, and her fourth, in 1992, to the retired Californian businessman Aubrey Ison, who died in 2007.
• Dinah Nadyejda Sheridan, actor, born 17 September 1920; died 25 November 2012
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