Elizabeth Spriggs, who has died aged 78, was a tall, blonde, elegant, fresh-faced and versatile actor. Her range embraced the leading stage companies in Shakespeare, George Bernard Shaw and JB Priestley; it took in television series such as Poirot (2006), Midsomer Murders (1997, 2006), and, notably, she was Nan in ITV's Shine on Harvey Moon, alongside Kenneth Cranham (1982-85). Her films included Work is a 4-Letter Word (1968), Sense and Sensibility (1996) and Harry Potter and the Sorcerer's Stone (2001).
Spriggs first came to prominence in the late 1960s with a run of acclaimed performances for the Royal Shakespeare Company, culminating in Peter Hall's 1969 production of Edward Albee's A Delicate Balance at the Aldwych theatre in London's West End. She played Claire, the hard-drinking sister of the female lead (played by Peggy Ashcroft), whose alcoholism does not entirely detract from her charm.
As a senior member of Hall's RSC, in 1968 Spriggs had played the Nurse to Judi Dench's Juliet in Romeo and Juliet, as well as Gertrude with David Warner as Hamlet and Mistress Ford in The Merry Wives of Windsor. Her persona had an underlying wholesomeness, creating sympathy for a variety of characters that might otherwise have outlived their welcome.
Spriggs was born in Buxton, Derbyshire, and educated at Wheatley Street high school for girls in Coventry. She was an unusually late starter as a professional actor, despite having a private coach in acting from the age of 11. She did not go to stage school but studied opera at the Royal School of Music. From an early age, she possessed a strong mezzo-soprano voice and her parents were open-minded about whether she should become a singer, a painter or an actor. Bronchial asthma ruled out being a singer, and though she chose the stage, she sometimes regretted not being a painter because a painter was free, whereas an actor was so dependent on the decisions of other people, an aspect of the job she always resented.
After training as a teacher of speech and drama, Spriggs took up a post at Coventry Technical College. She was at the same time a member of the local Little Players group. Aged 24, and now married, she applied for her first acting job, in repertory at Stockport. She was asked to come immediately. The theatre, the last one to survive in the town, was on the point of closing - indeed it closed seven weeks after she arrived.
Her next job was at the Grand Theatre, Halifax, which was also about to close. The director, approaching 60, played all the leading male roles and, though she was young enough to be his daughter, she once or twice played his mother. In 1953, the Bristol Old Vic followed and later came the Birmingham Repertory Company.
For the first 16 years of her career, she never once appeared on the West End stage. The reason, in her eyes, had been accidentally suggested by the legendary Sir Barry Jackson of Birmingham Rep, who was allowed out of his hospital bed in his last days to see her as Cleopatra in Antony and Cleopatra (1958). He told her that her greatest gift was versatility. This may have been so, and Sir Barry certainly meant it as a compliment, but she thought that her versatility meant that she was not a memorable type who could make a career in the commercial West End. It was certainly true that much of her career was to be spent in companies such as the National Theatre and the RSC, where her ability to switch between all sorts of roles was commercial as well as artistic gold dust.
The modern RSC was established by Peter Hall in 1960 and she joined two years later, finding at first that she was, as she put it with quiet indignation, "the only actress here who never wore a costume" - the reason being that she was constantly understudying. She was annoyed when actors in roles she dearly wanted played them no better than she could have done. But Peter Brook advised her to be patient and hang on because the RSC was the best organisation in the world to exploit her talents - which time proved. Her appearances had fresh air: alongside that golden run of 1968 performances were such triumphs as London Assurance, Twelfth Night, Major Barbara (all 1970), Othello (1971) and Misalliance (1986).
In her 1971 Much Ado About Nothing she at last played a powerful leading character, the spiky Beatrice. Analysing the way she would play this ambivalent role, caught between imperiousness and increasing love for the equally imperious Benedict, she thought in terms of painting: "A painter puts a great wash on and then he does things in detail; an actor does things in detail and then the whole thing has got to be coloured with a great big overall wash." In her case the resultant role was refreshingly open and "unstagey".
Joining the National Theatre in 1976, she appeared in Noël Coward's Blithe Spirit (1976) as the eccentric medium Madam Arcati. She also appeared in Macbeth, Ben Jonson's Volpone, William Wycherley's The Country Wife, Ödön von Horvath's Tales from the Vienna Woods and Arnold Wesker's Love Letters on Blue Paper (1978), which gained her an Olivier award for best supporting actress. JB Priestley's When We Are Married in 1986 saw her grace the West End, but for her Arsenic and Old Lace of 1991 she was at the Chichester Festival Theatre.
It was earlier, when she had been with the RSC for more than five years, and her career outside stage companies had yet to be launched, that she first came to the depressed, or at least irked, conclusion that part of her problem was age - not merely her own, but that of the characters she was called upon to play. She thought she had always been the wrong age. She had never played a juvenile, where she might have made a memorable impression, and recalled that even as a girl she had been putting "tramlines" on her face to play mothers rather than daughters.
She was now very aware of the passing of time, and wanted the London reputation denied to her after the success in A Delicate Balance, when the RSC had wanted her in Stratford-upon-Avon, "so out of love and loyalty to them I swallowed my disappointment and said I'd go".
Most of her later work was for television or film in supporting roles. Her other film work included The Secret Agent (1996), and Is There Anybody There? last year. Her television work also included A Christmas Carol (1999), Victoria and Albert (2001), Shackleton (2002) and Jericho (2005).
But she was happiest when appearing with a stable and continuing ensemble. In her eyes, this was something like being with a family. Her other-worldly quality had been expressed from childhood, when she talked to flowers and animals and was fond of reaching out and touching the people she was talking to - until an older girl told her that other people might not like being touched. The consequent inhibition was strange to her (she was to list her hobbies as "people and animals") and it was one of the reasons she took to acting, where she reasoned that she could reach people in a different and acceptable way.
Spriggs was married three times, to Kenneth Spriggs, Marshall Jones and, since the early 1970s, to Murray Manson, a classical guitarist. He survives her, as does Wendy, her daughter from her first marriage.
· Elizabeth Spriggs, actor, born September 18 1929; died July 2 2008