Michaels previously ran a similarly themed tour operation, Grave Line Tours, before moving to England in 1996, where, thanks mainly to his boyfriend, up-and-coming celebrity Graham Norton, he regularly rubbed shoulders with London's glitterati. Grave Line returned from the afterlife as Dearly Departed in January this year and has grown steadily, owing its success to painstaking attention to detail.

If you were to imagine a guided tour that combined the meticulous research of a Lonely Planet travel book with the dark humour of a James Ellroy novel, you would probably come up with something similar to Michaels' entertaining and often very funny three-hour odyssey around LA.

It's all there: the diner where James Dean tucked into his last meal and the garage where he collected the Porsche he was driving when he died; the crime scene of the 1969 Manson family murders; the soon-to-be demolished hotel in which Robert Kennedy was shot dead.

The tour takes in the side street where Hugh Grant was caught with prostitute Divine Brown in 1995, the public toilet in a posh Beverly Hills park in which George Michael was arrested for lewd behaviour, the Sunset Strip nightclub where River Phoenix had one too many with fatal consequences and, most recently, the news-stand from which Paris Hilton swiped a copy of her bootleg porn home video.

'Nothing is off-limits,' says Michaels. 'The only things I won't do are boring stories. O.J. Simpson is to me a boring story so I don't feature it on the tour. If people want to find out about that case then there are a million outlets for them to go to.'

Unsurprisingly, Michaels' name is not on everyone's Christmas card list. He's been spat at and had his car scratched while someone claiming to be an envoy of Jesus barked verses from the Bible at him near Dean's grave.

'I wait for the day when somebody comes up and tries to kill me,' Michaels says cheerfully. 'Because it pisses a lot of people off. When I appeared on television talking about O.J. I had people phone me up and say, 'I'm going to blow your head off', that sort of thing. But my thing is, if you don't want the attention, don't get famous. It's fairly simple really. Just because you die doesn't mean your fame ends. Generally though, the reception is pretty good. It's LA, after all, and we're just part of the tapestry.'

As an illustration of how closely Tinseltown's history is interwoven with the macabre you need only look as far as the famous giant Hollywood sign, which straddles the hills overlooking LA: British actress Lillian Millicent Entwistle leapt to her death from the top of the H in 1932, depressed at her failure to achieve fame and fortune.

Perhaps the most striking features of the tour are the countless examples of where the boundaries of real and reel life are blurred, where fact and fiction merge.

The 14-seat tour bus has barely pulled away from its pick-up point off Hollywood Boulevard before Michaels informs us that the nondescript looking hotel fire escape to our left is the very one that Richard Gere scaled to reach Julia Roberts at the end of Pretty Woman. ('That great Disney prostitution movie,' Michaels remarks wryly.) On a more grisly note, the hotel was also a home to Elizabeth Short, better known as the 'Black Dahlia', victim of one the most gruesome unsolved murders in LA's history. A movie based on the murder, starring Hilary Swank, is due out next year.

At one point, we sweep through an affluent, tree-lined neighbourhood that could be anywhere in moneyed, suburban America. That is until Michaels informs us that the mansion we are looking at is the one in which gangster Bugsy Siegel was shot dead in 1947. And that just around the corner is the house where Lana Turner's teenage daughter stabbed another mobster, Johnny Stompanato, to death in 1958. This leafy corner of Beverly Hills was also where eccentric tycoon Howard Hughes crash-landed his failing XF-11 aircraft in 1946 while attempting to set it down at the Los Angeles Country Club, a scene vividly recreated in Martin Scorsese's Oscar-nominated bio-pic The Aviator.

Not far away are the houses used for filming horror classics Halloween and A Nightmare on Elm Street. 'If you look hard enough, there's a story in almost every street,' says Michaels. But the landscape is changing quickly.

The Ambassador Hotel, the backdrop to presidential candidate Bobby Kennedy's killing in 1968, is to be knocked down this year. 'To me that's a shame. You're talking about destroying the scene of one of the standout moments of 20th century American history,' says Michaels. Other infamous addresses have already vanished. The home in Cielo Drive where Sharon Tate and four others were butchered by the Manson family in 1969 was bulldozed in the 1990s. The telephone pole that Charles Manson disciple Tex Watson shimmied up to sever communications to the house is still standing.

Michaels, meanwhile, speaks admiringly of the fact that Trent Reznor of rock group Nine Inch Nails had the door of the house - where the killers scrawled the word 'Pig' in blood - shipped to New Orleans and fitted in the group's recording studio. Can there be any possible justification for Reznor's ghoulish choice of furnishing, something most people would regard as sheer, out-and-out weirdness? Michaels thinks so.

'People might think that's creepy or sick but to me it's preserving an important part of LA history,' Michaels explains. 'Before the Manson murders, security wasn't an issue. Charles Manson practically created the security industry in Hollywood.'

After three hours, Michaels' tour winds towards its conclusion. But while it began with a landmark from Pretty Woman, the tour does not have a Hollywood

ending. The last spot on the scandal trail is the run-down apartment block in which rock star Dee Dee Ramone

died from a drug overdose in 2002. 'On his gravestone he had written, 'Okay ... I gotta go now',' says Michaels. 'I love that.'