Until last week Natasha Collins, a beautiful model and television actor, had dreamt of getting married to her “prince charming”, the BBC children’s television star Mark Speight. In a poignant entry on the Friends Reunited website, she described how she was planning to have “a huge fancy dress wedding . . . and no doubt have lots of monkeys” - her nickname for children.

That dream ended in tragedy last Thursday when Speight found her lifeless body in the bath at the couple’s penthouse flat in St John’s Wood, a leafy part of northwest London. Speight, who is known to millions of children for presenting the CBBC art programme SMart, immediately called 999. But when police arrived he was arrested on suspicion of murder and supplying a class A drug. He was released on bail.

Unconfirmed reports suggest that Collins, who had starred with Speight on See It Saw It, another CBBC show, had become unwell after an allnight cocaine binge. She was said to have stayed up until almost dawn snorting the drug. She took a few hours’ rest, awaking at lunchtime. She apparently felt unwell and went to the bathroom; her naked body was found by Speight at 1.20pm.

Yesterday Speight’s mother said her son’s fiancée might have died after taking drugs prescribed for a medical condition. Speaking through friends, Speight insisted that he had done nothing to harm her. Apolice source confirmed: “He did everything he could to save her. He was absolutely distraught afterwards and fully cooperative. He gave a full and frank account of what happened.”

If toxicology tests do confirm that Collins died from taking drugs, she will become the latest of a string of stars and lesser-known media figures who have suffered shame or tragedy from cocaine.

Earlier last week it emerged that another BBC presenter who died recently had apparently been taking drugs. Kevin Greening, a former BBC Radio 1 presenter, was reported to have died in his sleep, but police sources said his death had followed a dangerous sex game, allegedly fuelled by large quantities of cocaine, ecstasy and GHB, the date rape drug.

After those and other lurid headlines about BBC stars, the public might be forgiven for thinking that Auntie - and media work in general - attracts those with a propensity for the drug. But experts say the reality is that the well educated middle-class drug users of the BBC simply reflect a wider phenomenon: cocaine has become widespread among certain professions and across all classes.

Its toll is spreading. In 1993, when records began, there were 11 deaths from cocaine. In 2006 there were 190 in England and Wales, a record.

A DECADE ago Richard Bacon, then a host of the BBC show Blue Peter, was fired by the corporation after a tabloid caught him taking the drug. Lorraine Heggessey, then head of the BBC’s children’s programmes, made a formal televised apology.

In 1999 Johnnie Walker, a popular BBC radio disc jockey, was caught offering to supply cocaine to an undercover journalist. John Leslie, a Blue Peter presenter for five years from 1989, played the starring role in one of the biggest TV scandals of recent times. He was caught up in allegations - later dropped - of sexual assault, and in 2002 video footage emerged of him snorting cocaine.

Behind the clean-cut onscreen personas, the stars treated cocaine as a drug that was almost normal to use. Collins, who came from a comfortable background, seems to have been drawn into a similar lifestyle. Yesterday, former schoolmates at St Michael’s Convent Catholic grammar school in north London described her as very popular.

Carla Gediking said: “We were in the same class for all of our subjects right up until the sixth form. She was a very popular girl. She was one of the ‘pretty girls’ in the year and she was really lovely.”

Lynsey O’Donnell, head of advertising at her casting agency HandE, said: “She was beautiful. But she was also lovely. I’ve spoken to photographers who said they loved photographing her because she’d got such a big smile.”

Collins embarked on her career 10 years ago, making her television debut on See It Saw It. It was there that she met Speight. With his trademark spiky hair, Speight, 42, has been a children’s television stalwart since he began presenting SMart in 1994. Colleagues described him yesterday as a “party animal”.

Clive Doig, managing director of Bechin, the independent television production company which made the show for three years from 1998, paid tribute to the high hopes that colleagues then had for Collins. “She was a very good young actress and she was a lot of fun to work with,” he recalled. Collins had played See - a court jester to the king, who was played by Speight.

However, her life was shattered after a road accident - she admitted “running into a moving car”. It happened only a year after she had lost her father. Friends say that from then on her life seemed dogged by misfortune and illness. She became painfully thin. Her television career petered out and she took to modelling. Her last job, friends say, was modelling for a mattress company on the internet.

Whether her misfortunes played a part in her apparent use of drugs is not known. But experts say that the pressures of the media industry make its participants particularly susceptible to drug use.

Deborah Cameron is chief executive of Addaction, the drug charity. When she steps out of her office after working late on a Friday night in Farringdon, one of the main media districts in central London, she is struck by the number of television producers and media executives who are high on drugs and alcohol. These are not the type of addicts that Cameron’s charity helps.

She says that the television professionals who use cocaine do not consider themselves to have a drug problem. They hold down high-pressure jobs and do not steal to feed their habit. They work extremely long hours and are often considered to be successful at what they do. Taking cocaine has simply become part of both their professional and social lives.

Unlike heroin, cocaine is often seen as a “clean” - and therefore safe - drug. For those in the limelight, the adrenaline rush helps them to appear bubbly and full of personality, even when they feel exhausted.

Cameron said: “Heroin slows you down and makes you sleepy. Cocaine speeds you up, makes you excitable and enjoy things. People who are worried about their deadlines believe cocaine can help to meet them. You feel that you can carry on with your work without being affected. You do not realise that you are becoming aggressive and that your judgment is becoming affected unless someone else brings it to your attention.”

COCAINE is not confined to media types. Also known as “snow” or “Charlie”, it has become the most fashionable drug for young Britons, replacing cannabis, amphetamines and ecstasy.

There are more young users in Britain, as a percentage of the population, than in any other developed country, including the United States. A report by a Lisbon-based European drugs monitoring agency said that 4.9% of young people in Britain used the drug.

The problem is seen as so serious that on his first day in office in 2005, Sir Ian Blair, the Metropolitan police commissioner, vowed to target middle-class cocaine users who snorted the drug at dinner parties. Critics dismissed Blair’s comments as overblown. But he was reflecting deepening government concern at the grip that the drug was taking at all levels of British society - and its cost.

More than 10,000 people are being treated for their habit on the National Health Service. Cocaine has surpassed heroin as the most widely used class A drug in England and Wales, which also have the second-largest number of adult cocaine users in Europe, after Spain. According to figures from the NHS Information Centre drug misuse report, 7% of adults reported having used cocaine during their lifetime. Four times more adults now admit taking the drug compared with 10 years ago.

Health workers say users ignore the dangers. Snorting cocaine can damage the membranes in the nose; it also raises the heart rate and blood pressure. In the long term, cocaine users can develop heart problems and chest pain. Heavy use can lead to convulsions, confusion and paranoia.

Not everyone in authority believes that the drug is dangerous. In an interview with The Sunday Times today Richard Brunstrom, chief constable of North Wales police, repeats his call to legalise drugs, including cocaine, heroin and ecstasy.

“Why are heroin and cocaine illegal and not lighter fluid?” he asks.

This weekend Speight was said to be too distressed to talk publicly about the death of his fiancée. He will be waiting for the results of tomorrow’s postmortem examination.

Additional reporting: Anna Mikhailova and Chris Thompson

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