But in 1957 he managed to secure his reputation as an actor with a fine performance in Sweet Smell of Success (1957). His portrayal of the sleazy, unprincipled publicity man Sidney Falco surprised critics who had previously dismissed him as nothing more than eye-candy.  Two years later Curtis managed to combine his looks and acting talent in the film for which he will be best remembered, Some Like it Hot. His partnership with Jack Lemmon produced some of film comedy's most memorable lines, delivered with panache and perfect timing. Indeed, Lemmon and Curtis took such effort with their roles – of two musicians who disguise themselves as women to escape the attentions of Mob assassins – that they tested their outfits for authenticity by using the ladies' lavatory during filming.  "We felt really self-conscious," Curtis remembered, "but it was important that we looked real enough to pass for women. After all, in the film our lives were supposed to depend on it."  While Curtis's professional life was at its peak, his private life began to disintegrate. Severe hypochondria resulted in his seeing a psychiatrist regularly in the early Sixties, and his dependence on drugs and alcohol became public knowledge. His career began to slide, and during the Sixties and Seventies he made a series of forgettable "sex-comedies". Despite a serious attempt to rescue his reputation in 1967, when he gave a good performance in The Boston Strangler, he found himself stranded in second-rate films or television series such as The Persuaders.  By the early Eighties Curtis was drawing attention to his drink and drug addiction by his eccentric choice of clothing. Typical day wear included ankle-length capes with wide-brimmed hats, but on special occasions he preferred an Arabian djellaba teamed with Dutch clogs. On one occasion he greeted visiting reporters in an ex-Army beret, underpants and long socks. "Drugs do terrible things to you," he recalled, "you think you're being charmingly out of the ordinary when in fact you're being a bore." Curtis was finally forced to enter the Betty Ford Clinic after suffering from severe cirrhosis.  In 1985 he surprised his critics by recovering sufficiently from what he described as his "illnesses" to return to making films. He played the corrupt senator in Nicholas Roeg's Insignificance, and the following year returned to television in a series called Spies. In later life he moved out of Los Angeles and spent most of his free time painting nudes.  He was born Bernie Schwartz on June 3 1925, the son of an impoverished Hungarian immigrant, Manny Schwartz, who had himself arrived in New York with hopes of making it as an actor. Unable to speak the language, Manny Schwartz found a tailoring job and remained in the Bronx with his family. Bernie grew up in a predominantly Hungarian-speaking part of the Bronx, and recalled that he did not learn to speak English until he was seven years old.  At 12 he spent his days playing truant and working as a shoeshine boy outside Bloomingdale's department store. He supplemented his income by throwing himself under the wheels of oncoming traffic, pretending to be injured, then begging for the taxi fare to hospital. At night he spent most of his time stealing from shops and bars. "I was a real delinquent kid," he recalled, "but acting put me on the straight and narrow."  Encouraged by his father, who wanted his son to succeed where he had failed, Bernie attended a summer camp for troublemaking boys and took up acting. He became so enamoured of his new interest that he volunteered to appear as Guinevere, in a wig and dress, in the end-of-camp performance of an Arthurian tale.  At 17 he joined the Navy, signing on for three years. But his hopes of promotion were crushed when he was told that he did not have good enough school marks for officer training. "I couldn't believe it," he recalled, "these guys were telling me I was real dumb." After leaving the Navy, he took advantage of the Forces Educational Scheme and enrolled in high school to complete his education.  He continued to act, first (in spite of parental disapproval) with the YMCA, and later with a Jewish theatre company. In 1945 he was playing the lead in Golden Boy when he was spotted by a talent scout for Universal, which immediately signed him on a seven-year contract.  He moved to Hollywood where, despite regular income from the studio, he found himself on the brink of poverty. After paying for membership of various performing guilds, buying a new wardrobe and paying agent's fees he was left with $1.50 a week.  The actress Shelley Winters recalled that Tony Curtis arrived at her flat one afternoon at this time, and introduced himself as Bernie. "My mom knows your aunt back in the Bronx," he said, "and she said you should take care of me until I get settled." Shelley Winters found him an apartment to share (with Marlon Brando) and introduced him to her friends – including Marilyn Monroe, whom Curtis immediately asked out.  Universal decided that Bernie Schwartz was not a "bankable" name, so Curtis chose Antonio Cortez. When Universal again complained that the name was too "Latin", he changed it to Curtiz and eventually Curtis. He made his screen debut in 1945, dancing a 15-second Mambo with Yvonne de Carlo in Criss Cross, which starred Burt Lancaster.  Universal was uncertain how to market Curtis and pushed him into a number of small parts playing hoodlums. It was not until the publicity department inadvertently released a bare-chested shot of Curtis looking moody that he began to gain popularity. The office was instantly swamped with letters from female fans wanting to know more about him.  From then on Curtis was marketed by Universal as a sex symbol. They ignored any talent he had and cast him in a series of "Easterns" and costume dramas, including The Prince Who Was a Thief (in which he uttered the now famous line: "Yonda lies da cas'l of my fadda da caliph"). To his credit, Curtis played the "tights and pumps" parts with verve and a light comic touch.  Throughout the rest of the Forties and Fifties, Curtis continued to appear as princes and sultans in a variety of adventure films. He put his athletic abilities to good use for the first time in Trapeze (1956) as the eager young trapeze artist. The film starred Lancaster, who had invested his own money in the project and persuaded Curtis to do the same. It was a major success, and led to Curtis's third appearance with Lancaster, in Sweet Smell of Success.  Both Lancaster and Curtis were excellent as, respectively, the gossip columnist JJ Hunsecker and his ambitious sidekick, Sidney Falco. Directed by Alexander MacHendrick to a jazz score by Elmer Bernstein, the film was acclaimed for its acid exposé of the corruption at the heart of New York nightlife.  A year later Curtis was nominated for an Oscar for his performance in The Defiant Ones, which co-starred Sidney Poitier. Despite Curtis's mammoth list of credits (with appearances in more than 130 films), this was to prove his only nomination. He did not win. "It was a token nomination," he recalled, "a Jew and a black guy."  But any disappointment was soon forgotten when Curtis then appeared as Josephine, the saxophonist on the run in Some Like It Hot, which has gone on to feature in almost every round-up of all-time great pictures. Before filming, Billy Wilder employed a female impersonator to teach Curtis and Lemmon how to walk and sit like women. "You have to let go of all your muscles," Curtis remembered, "otherwise they look too defined. You need to look slinky, supple."  Curtis remembered filming itself as a difficult period: he had problems with Wilder and was unhappy about his co-star Marilyn Monroe's appalling timekeeping and petulant manner. "By the time she made that film Marilyn was like a mean six-year-old kid," he said. "It took 42 takes for one line. Wilder would always take Marilyn's best scene, no matter how bad Jack or I were; if Marilyn was good he printed it."  With Lemmon getting the funniest lines, and Monroe singing great songs, Curtis's performance was largely overlooked by critics. But he produced some of the most subtle acting in the film, playing three roles: a musician, a woman and a ridiculous millionaire. The latter part was modelled, at Curtis's suggestion, on Cary Grant, a lifelong hero. "Nobody talks like that," Lemmon's character says in the film. But when Grant saw it he turned to Curtis and asked: "I don't talk like that, do I?"  Tony Curtis recalled that he based his character of Josephine on a combination of his mother and Grace Kelly. "I wanted to look aloof and stylish," he remembered, "Josephine was not going to be the kind of broad who came across for just anybody. Now Daphne [Jack Lemmon], for a two-dollar bill she'd go with anyone."  After Some Like It Hot Curtis had the opportunity to work with Cary Grant in Operation Petticoat, a nautical farce with Curtis as a crafty junior officer. He had also taken the lead role in The Vikings, which co-starred Kirk Douglas, and in 1960 starred opposite Douglas again in Stanley Kubrick's Roman slave epic Spartacus.  The film includes a controversial scene in which Laurence Olivier's Crassus attempts to seduce Curtis's character. Later, it is Curtis who, after the on-screen defeat of the slave armies, when Crassus is seeking to identify the rebel leader, stands up and shouts: "I'm Spartacus" – leading to a famous chorus of similar claims from all the captured men.  "I really must have done something right to appear in all those great movies," Curtis said afterwards. "I was just a wise-ass Jew kid from the Bronx. I end up in Billy Wilder's best movie, Lemmon's, Monroe's and Kirk Douglas's best movie."  Although Curtis's career was very successful in the late Fifties, the same was not true of his private life. Such was his hypochondria that Universal had had to heat the water falling on him in any "rainstorm" scenes due to his fear of catching a cold. By the mid-1950s he was seeing a psychiatrist three times a week. When he went to Paris to film Trapeze he sailed to France because he had developed a fear of flying. Such problems were not helped by his dependence on drugs and alcohol. "I took everything," he remembered, "uppers, downers, dope, heroin and cocaine."  By the early Sixties Curtis's marriage to Janet Leigh (publicised as Hollywood's happiest) was in serious difficulties. The couple separated, and Curtis started an affair with 17-year-old Christine Kauffman. When Kauffman became pregnant in 1963, Janet Leigh divorced Curtis and he married Kauffman.  Soon his career ran into trouble too. While he continued to appear regularly in films, he did not match his earlier performances. By the middle of the decade he was appearing in tepid comedies such as Paris When it Sizzles and Wild and Wonderful (which starred a French poodle). A nice piece of casting in The Great Race (1964) could not save Curtis's reputation, and he began to appear solely in vapid sex-comedies such as Sex and the Single Girl, Boeing Boeing and Not With My Wife You Don't.  By the late Sixties Curtis was worried about his future. But in 1967, the year that his four-year marriage to Christine Kauffman ended, he went some way towards redeeming his reputation when he appeared in The Boston Strangler. Curtis had not been an immediate choice for the part, but after reading the script he put on a false putty nose, dragged his hair over his face and took a series of "mug shots" with an instant camera. He sent the photographs to the director Richard Fleischer, who did not recognise him; when Curtis later telephoned and expressed interest in the role he was cast as the murderer.  Despite the success of his performance in the film, Curtis's career was by no means secure. As the decade drew to a close he appeared in another series of forgettable films, among them Suppose They Gave a War and Nobody Came and You Can't Win 'em All.  During the 1970s his career appeared to take on a degree of stability, with a role in the television show The Persuaders, which took his celebrity from the cinema into every household. Once again he found his way into a good film when he was cast in an excellent cameo role as the impotent and ageing matinee idol in Elia Kazan's The Last Tycoon, which starred Robert Mitchum and Robert de Niro. But the majority of the projects to which he signed up were undemanding, and all too often he found himself in roles for films such as Bad News Bears Go to Japan (1978).  Curtis's combination of drug addiction and alcoholism soon became so problematic that even those who did not know him realised that he was behaving unusually. He started giving interviews to the press while lying on the floor of his hotel room, and repeatedly asked interviewers if they thought he looked handsome. In 1984, after being rushed to hospital with advanced cirrhosis, he checked into the Betty Ford Clinic. On leaving he promised to wage a battle against "my various illnesses". Though he gave up cocaine and alcohol, he claimed it was much harder to overcome his "addiction to women".  At the age of 60 Curtis had a relationship with a 17-year-old topless model, Debbie Ashby. The affair was a sensation in the press, and in a "kiss and tell" interview Debbie Ashby claimed that Curtis spent most of his time resting in bed. "He wanted company. It wasn't just my boobs," she insisted. "He said I had an interesting personality." She remained at Curtis's house for two weeks, spending most of her time making cups of tea. "He kept asking me if I liked him," she recalled, "he said he couldn't tell any more if people really liked him, and he kept crying."  To the surprise of critics, Curtis revived his career in the mid-Eighties, appearing as the senator in Nicholas Roeg's excellent Insignificance (1985). The film dealt with a variety of American stereotypes, the actress (Monroe), the scientist (Einstein), the baseball player (Joe DiMaggio) and the senator (McCarthy). "I was lucky I got that role," Curtis recalled, "it was as important to me as Sidney Falco in Sweet Smell of Success."  For the next few years his eagerness to appear in films hardly seemed to waver. "If they offer me good parts, I'm going to do it, put on my trunks and gloves and kick the shit out of it." But titles such as Lobster Man from Mars and Tarzan in Manhattan (both 1989) did nothing to suggest that he was about to make a return to his best.  Increasingly he devoted himself to his painting, claiming Magritte and Matisse as influences. His autobiography, American Prince: A Memoir, appeared in 2008.  Tony Curtis married six times; his last wife, Jill Vandenburg Curtis, more than four decades his junior, survives him. Towards the end of his life he said that, despite his many marriages, he was reconciled with his many children and grandchildren. "I'm lucky that my kids like me again," he said, "I want to have a dynasty that lasts for ever." One son, Nicholas, predeceased him in 1994 after overdosing on heroin aged 23, a blow from which Curtis said he never recovered. The actress and author Jamie Lee Curtis is his daughter by Janet Leigh.
Tony Curtis, who died on September 29 aged 85, was one of Hollywood's last    matinee idols; the product of a classic success story, he rose from a New    York ghetto to enjoy fame and stardom that was largely unparalleled for much    of the 1950s and 1960s.