The mysterious death of the American singer Dean Reed, known as the Red Elvis, has had conspiracy theorists speculating about the hand of the KGB or the CIA for 20 years.

Virtually unknown in the West, Reed, 47, was a superstar in the Soviet empire. Mobbed by Russian fans in Red Square, he danced the twist in Minsk and topped the charts in Bulgaria and Hungary. Then in June 1986 he was found drowned in a lake in East Berlin, where he had lived since 1971.

Now a documentary that had its premiere at the Berlin Film Festival last night suggests that Reed was not the victim of the spy services of East or West, nor of a tragic accident — the version peddled by nervous East German media — nor even, as some believed, of a jealous husband. Rather, the hero of Soviet teenagers killed himself, deliberately donning two jackets on a summer night so that the currents would drag him under.

“He couldn’t see a way out,” Leopold Gruen, the director, told The Times. “He wanted to go back to the United States but realised there was no return. At the same time, the socialist ideals that had brought him to the East had fallen by the wayside.”

Reed’s socialism was rooted in the 1970s — he once sang proudly in the private railway carriage of a Kremlin politician — and Mikhail Gorbachev’s reforms looked about to shake up his world.

Born in Denver, Colorado, in 1938, Reed was neither a good actor nor a particularly good singer, but he arrived in Eastern Europe at the right moment: communist chiefs were looking for a cult figure, a left-wing rock star who could stir youthful enthusiasm for a stagnant system. His first hit was a version of Elvis’s Blue Suede Shoes.

His Western singing career had never taken off, but he was very popular in the Chile of the Marxist Salvador Allende and his anti-Americanism, combined with clean-cut good looks, caught the attention of Soviet talent-spotters.

At the Leipzig Film Festival in 1971 he met his second wife, an East German, and made the country his base. It was seen as a huge propaganda coup by the communists and his records were produced by the millions in Moscow studios.

The Stasi secret police arranged a flat as a love nest for his mistresses and he was flown around the world to sing We Shall Overcome to dispossessed farmers. “I was sure we had got ourselves a Hollywood star,” says Egon Krenz, the last leader of East Germany, in the film Red Elvis.

That remained the central misunderstanding: the communists thought, wrongly, that they had netted a world-class perfomer, while Reed thought that he had found his true revolutionary home. “It was a classic tragedy,” said Mr Gruen, “ a story of naivety.” The crumbling of his illusions — and the curdling of his marriage — drove him to suicide. Perhaps it is this unhappy combination that has inspired film-makers and writers.

Apart from Mr Gruen’s film, Tom Hanks is planning to direct a Hollywood version of Reed’s life based on the book Comrade Rockstar, by Reggie Nadelson. A CD of his best songs has been released and a new biography was published last year. Mr Gruen said that there would probably be no definitive answer to the riddle of Reed’s death. An Eastern intelligence service could have killed him rather than let him return to the US but that would have been a serious risk. So suicide is Mr Gruen’s explanation. “Suddenly there were too many cul-de-sacs in his life,” says the director. “He felt trapped.”

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