At the pinnacle of her career Joan Turner became the highest-earning female singer and comedienne in the country, with a recording contract, her own radio and television shows, and a one-woman cabaret show in which she toured Britain and the United States; in 1980 she appeared at the Carnegie Hall in New York. In London she was the star of Royal Variety Shows at the Palladium and in West End musicals.   As she became overwhelmed by personal problems, however, she disappeared from view; and in 2001, when she was 79, she was unearthed in Los Angeles, shuffling along Sunset Boulevard,  still nurturing a hope that she would break into Hollywood.

Joan Turner strove to put a brave face on her reversal of fortune, which, in a Channel 4 documentary screened that year, she sought to represent as more of an adventure than a catastrophe. But there was no disguising her drink problem. “I just couldn’t give it up,” she confessed. “I was down to, like, three dollars. You lose a bit of hope, you know, when you run out of money.” All that stood between her and destitution was her British state pension of £50 a week,   Once described as possessing the “the voice of an angel and the wit of a devil”, Joan Turner was an artist of impressive versatility. With a soaring voice that could encompass four and a half octaves, she could handle operatic arias, perform impressions – her repertoire included Gracie Fields, Shirley Temple, Bette Davis, Vera Lynn and even George Formby – and rattle out stand-up comedy routines. It was a range of talent that earned her the accolade of “the female Harry Secombe”, and the critic Jack Tinker crowned her “the greatest of the old time funny ladies”.

But although she appeared to have the world at her feet in the 1950s, Joan Turner’s drinking and gambling addictions were becoming common knowledge in showbusiness circles. She enjoyed the company of the biggest stars of the day, and boasted of an amorous encounter with the actor Peter Sellers when they were both appearing at Bridlington in 1952. “It was in the bushese_SLps and over in a flash,” she noted while preparing her unpublished memoirs.   Her other claimed conquests included the magician David Nixon as well as the comedians Tony Hancock and Terry-Thomas, both of whom, it seemed, were too drunk to consummate matters.

Joan Theresa Turner was born in the Falls Road, Belfast, on November 24 1922, the daughter of a Roman Catholic British soldier serving in Northern Ireland. In the course of a street battle during the Troubles which had spread from the south, a stray bullet narrowly missed the infant Joan, asleep in a makeshift cot, and lodged in a drawer an inch from her head.   After her family had returned to London, her father found work first as a bus driver and later driving a taxi. Joan, meanwhile, having won a scholarship to the Sacred Heart convent in Victoria, defied the mother superior by abandoning her education aged 14 to go into showbusiness, soon landing a spot in music hall. Parts in revue shows followed.   Having cut her teeth on working men’s clubs in the north, she established herself as a formidable comic talent. She became one of the stars of the anarchic comedy group the Crazy Gang, appearing with them in their long-running show at the Victoria Palace and in the Royal Command Performances of 1954 and again in 1963. On the latter occasion she appeared alongside the up-and-coming Beatles, above whom she had been given star billing at the Grosvenor House Hotel in the group’s first London cabaret show. She had featured roles in the West End hits Oliver! and Call Me Madam and starred at the Talk of the Town.

Throughout this period Joan Turner had struggled to control, or at least to contain, her alcoholism. She joined Alcoholics Anonymous, and found herself in rehab alongside George Best, Tommy Cooper and George Peppard. But her problems with drink and gambling (she was particularly addicted to playing the one-armed bandit) deepened. In 1977, after a final royal engagement to celebrate the Queen’s Silver Jubilee, Joan Turner was declared bankrupt. The following year, when she was appearing as Mrs Bumble in a West End revival of Oliver!, she was sacked for hurling empty wine bottles out of her dressing-room window at the Albery Theatre.   During the 1970s she had toured her own show, Joan Turner Unlimited, throughout Britain, and in 1980 she took it to America, where she lived, drank and – sporadically – worked for seven years.   On her return to Britain, an award-winning appearance in The Belle of Belfast City at the Contact Theatre, Manchester, led to her being cast in 1991 as Aunty Lou in the Liverpool-based Channel 4 soap Brookside. But she was drinking heavily again, and was fired within a few weeks.

By 1996 she was back in the United States, still hoping to kick-start her career in Hollywood. She auditioned unsuccessfully for the Palm Springs Follies, a troupe of dancers aged 60 or more, and then spent two years in Las Vegas, with the inevitable result: “I couldn’t stop gambling.” She eventually returned to Los Angeles by Greyhound bus, her savings reduced to less than £50.   Slumped on a pavement on Skid Row, alone and penniless, Joan Turner mixed with down-and-outs and drunks before eventually being taken in by Catholic nuns who ran a hostel for the homeless. In 2001, after her plight had been featured in British newspapers, her daughters paid for her flight home.

Joan Turner appeared in three films: Alan Bleasdale’s No Surrender (1985); Scandal (1989), in which she had a cameo role; and Louisa and the Jackpot, which starred Oliver Reed but has never been released.

She made her final television appearance in 2004, as Mrs Sunnelly in the ITV crime series Commander II, created by her friend Lynda La Plante. Her last live comeback attempt, at a small London theatre that summer, ended in a drunken shambles.   Joan Turner spent her final years in sheltered accommodation in Surrey where, with the actor Harry Dickman, she worked on a poignant autobiography called I Thought It Grew on Trees and spoke of her “adventures” as a down-and-out in Los Angeles. The book awaits a publisher.   In 1992 Lynda La Plante wrote to Joan Turner: “Nothing will ever take away your extraordinary talent, a talent that is as fragile as a bubble. It floats in its unexplainable way from inside you, like the child you still profess to be. You stand, and laugh, and make everyone want to laugh with you. It is precious in its simplicity.”

Both Joan Turner’s marriages – to a solicitor, Christopher Page, and to a record company executive, Les Cocks – ended in divorce. Her three daughters survive her.

Her “Telegraph” obituary can also be accessed here.