STALKER SQUAD; TINSELTOWN A-LISTERS INCLUDING BRAD PITT AND BRITNEY HAVE REASON TO BE GRATEFUL FOR FORCE'S THREAT MANAGEMENT UNIT They're the LAPD detectives who spend their lives protecting Hollywood's biggest stars from crazed fans and these fearless cops are busier than ever.
FOR a celebrity there are few more dangerous places in the world than Los Angeles.
The epicentre of the Hollywood dream factory also attracts its share of lunatics, obsessed with the stars and desperate to make their twisted fantasies a reality.
"There is a fine line between fan and fanatic," says Jeff Dunn, from the Los Angeles Police Department. "Today they've got access to a telephone and a computer and they can make our victims' lives a living hell."
Dunn is part of the "threat management unit" which handles star stalkers who've gone over the edge.
Among the stars threatened are actress Jennifer Garner, who recently got a restraining order against a man who blogs about human sacrifice. He has terrorised her since 2002.
Michael Douglas' stalker, Dawnette Knight, threatened to cut up the actor's wife, Catherine Zeta-Jones, and feed her to her dogs, while Uma Thurman describes her experience with stalker Jack Jordan, as a nightmare.
And no Hollywood star is immune from the threat. Anthea Rolando was so in love with Brad Pitt, she once broke into his home, fed his dogs and even slept in his pyjamas.
The LAPD's Threat Management Unit was formed in the wake of a star's sickening murder at the hands of a stalker in 1989.
Rising star Rebecca Schaeffer had a lead role on smash American TV show My Sister Sam. Schaeffer was butchered by Robert Bardo, an obsessed fan who was madly in love with her.
The slaying stunned Hollywood, and at the time there were no stalking laws in California or anywhere else.
Schaeffer was gunned down at her front door. For cops, her brutal death was a wake-up call.
"Rebecca Schaeffer had to be the victim of a homicide in order for us to get the message that something needed to be done in the way of legislation to address stalking crimes," said Dunn.
Twenty years on, few know the terror of a crazed stalker better than pop princess Britney Spears.
In 2003, Spears was followed by obsessed fan Masahiko Shizawa who embarked on a 37-date tour in pursuit of the pop star.
Dunn said: "He was a Japanese businessman who came to America to follow Britney Spears around on her concert tour. As far as Britney was concerned, he was completely delusional."
Shizawa used the internet to track Spears' concerts and every aspect of her life from Louisiana to Los Angeles, with chilling results.
Dunn said: "He was in very close proximity to her at several points.
"There's a picture of her limo as she is leaving a show. On the back of the photo he says 'I'm chasing you.'"
Shizawa also believed he had a relationship with Spears.
Dunn added: "We knew there was going to be a long-term problem until she dealt with it."
Advised by the stalking unit of the potential danger, Spears got a restraining order.
And when Shizawa's tourist visa expired, that restraining order was used to get him on a no-fly list.
He's tried to re-enter America five times, but luckily he's been stopped.
Expert Reid Meloy says the average star stalker case lasts about 16 months, but he's seen them go on as long as 15 years.
In the past 20 years he has seen an increase in murderous stalkers.
He said: "Violence among celebrity stalkers, if it is carried out, is usually planned and purposeful."
Besides Schaeffer, John Lennon was murdered by a stalker, while others, such as Monica Seles, were stabbed.
And with the man believed to have murdered Jill Dando, Barry George, having had his conviction quashed, a question mark remains over who killed the Crimewatch presenter.
But Dando isn't the only British star to have been targeted. The list of famous faces who have been the victims of stalkers reads like a celebrity who's who.
George Michael, Charlotte Church, Colin Firth, Keira Knightley, David and Victoria Beckham, Sir Ian McKellen and Cheryl Cole have all had stalkers.
And in January, 66-year-old Sandra Price was given a 12-month suspended sentence after being found guilty of harassing actor Martin Shaw over a five-year period. The pensioner believed she was able to help Shaw get over the breakdown of his marriage, sending letters and tapes to the star, while compiling a huge dossier on him.
She moved from her home in Yorkshire to live in the same village as him in Norfolk, was spotted outside his house, and was only arrested after she poured petrol through Shaw's girlfriend's letterbox.
It's stories such as this which led to the UK setting up its own version of the LAPD's Threat Management Unit.
Based in London, the Fixated Threat Assessment Centre uses police officers and psychiatrists, and helps around 1000 people a year.
Its aim is to "assess, manage and reduce potential risks and threats from fixated individuals, against people in public life."
Research based on 8000 files compiled by the Metropolitan Police between 1988 and 2003 found in the cases judged to be genuine instances, 80 per cent of those responsible had some form of mental illness.
It's a statistic that comes as no surprise to police in Hollywood. One stalker considered to be extremely dangerous by both Reid Meloy and LAPD, was Jonathan Norman.
Dunn said: "He had a plan to kidnap and sexually assault Steven Spielberg."
Norman tried to pass himself off as the ET director's adopted son, but from his twisted journal entries, it's clear his motives were more sinister.
He wrote: "I would force him to put on a screening muzzle, and then put handcuffs on him with his hands in front of him.
"I would then have him direct me to his apartment and then cuff and gag any roommates he might have."
Norman was sentenced to 25 years to life.
Eighties star Morgan Fairchild played a stalking victim in the movie The Seduction, but even she has faced the threat for real, recently shaking off an obsessed woman with the help of the LA-based unit.
She said: "Different people who have had female stalkers you tend to view it as less threatening in a certain kind of way, but they can be just as lethal."
Fairchild then added that the troubled woman thought the star was her mum.
Robert Hoskins, one of the most dangerous stalkers on record, was the man who scaled the security walls of Madonna's estate trying to get to the singer.
He thought Madge was his wife, but Madonna's bodyguard luckily intervened.
Dunn said: "The thing that makes Hoskins so dangerous is he believed Madonna's spirit could inhabit anyone at any given time.
"If Robert Hoskins was walking the streets today and he decided that you or I were Madonna, we would be at grave risk.
"We've got to keep guys such as this in custody for as long as we possibly can."
'Rolando was so in love with Brad Pitt, she once broke into his home, fed his dogs and then slept in his pyjamas'
'Hollywood actress Uma Thurman described her experiences with stalker Jack Jordan as "a nightmare"'
BRITNEY STALKER MASAHIKO SHIZAWA; BRAD STALKER ANTHEA ROLANDO; UMA STALKER JACK JORDAN; CATHERINE STALKER DAWNETTE KNIGHT; GOOD JOB: Jeff Dunn is keeping the stars safe