DURING the 1940s, Kay Walsh was one of the most familiar faces in British films, as well as one half of British cinema's most glamorous couple. In addition to appearing in such popular films as In Which We Serve, she was also the second wife of David Lean, whose career as a director she helped and encouraged. Indeed, it was Lean who gave her her most famous roles - as Queenie, the rebellious daughter in the soap opera-esque wartime drama This Happy Breed (1944) and as Nancy in OliverTwist (1948).

But there was more to Walsh than her ability to create memorable characters. She devised some of the most striking scenes in two of her husband's most acclaimed films. It was she who came up with the ending of Great Expectations (1946) - which many think better than Dickens's own - and it was she who dreamed up the unforgettable opening sequence of Oliver Twist, in which a young woman about to give birth struggles across a windswept moor. The scene, filmed exactly as Walsh had sketched it, features haunting shots of jagged, thorny branches silhouetted against the night sky; the perfect images to represent the contractions experienced by Oliver's mother. As she reaches a gate, the audience, believing that she is home, heaves a sigh of relief.

But the camera pans up to reveal that the gates belong to the Parish Workhouse.

Born and raised in London, Walsh was a keen dancer as a child and began her showbusiness life as a chorus dancer in revues before making her film debut in the musical How's Chances (1934).

She learned how to act on the job, as she was flung into a stream of B-movies. In 1936, she met Lean, who was then working as an editor. Her career took off shortly afterwards, when she was spotted by the Ealing producer Basil Dean while she was appearing in a West End play. Dean gave her a year's contract and two high-profile roles, both opposite the entertainer George Formby, in Keep Fit (1937) and I See Ice (1938).

After living together for almost four years, Walsh and Lean were married in 1940.

They had already unofficially worked together (Walsh wrote some additional dialogue for Pygmalion, which Lean edited) when they both landed jobs on the Noel Coward war drama In Which We Serve (1942). Coward thought that Walsh's "nice, mousey quality" made her perfect for the part of John Mills's girlfriend. In real life, however, Walsh was far from mousey, and it was she who put Lean up to asking Coward for a shared directing credit.

By the time she appeared as Nancy in Lean's classic version of Oliver Twist, Walsh was settling into her role as one of the country's best character actresses. She was considerably less proud of her performance in the film (her Nancy is not as "damaged" as she would have liked) than she was of the behind-the-scenes part she had played: not only had she devised the opening sequence, which had been causing concern to Lean, but she also found him his Artful Dodger, in the shape of her young colleague from the comedy Vice Versa - Anthony Newley.

Through the 1950s and 1960s, Walsh - who divorced Lean in 1949, citing his adultery with the actress Ann Todd, and married the noted psychologist Dr Elliott Jacques - popped up as interesting characters in a wide range of films, including the Alfred Hitchcock murder mystery Stage Fright (1950), which starred Marlene Dietrich, the historical drama Young Bess (1953), the Disney tearjerker Greyfriar's Bobby (1961), and several Alec Guinness vehicles, among them The Horse's Mouth (1958) and Tunes of Glory (1960).

Kay (Kathleen) Walsh, actress; born August 27, 1911, died April 16, 2005.