Perhaps even more fantastically, Lucy had written a letter to her friend in which she described what she called her "Life Plan". This was a wild fantasy which involved smoking "loads of drugs, more and more drugs as time went by", and would lead eventually and inevitably to addiction to crack cocaine.
Lucy's friend told Birmingham crown court on Wednesday that at first she did not believe her, thinking it was just an example of her schoolmate's sense of humour. There was, however, more substance than invention in the schoolgirl's claims. An outline of the deliberate, seemingly pointless descent of Lucy from successful student to a parallel life on the streets, taking soft drugs and swapping school clothes for her prostitute's "uniform", has been unfolding at a trial into her death by a drugs overdose. Two men, Tahir Khan, 27, and Rungzabe Khan, 25, both from Birmingham, deny giving her heroin and murdering her in August last year. The case is continuing.
What was striking in the revelations about Lucy's turning to prostitution was just why she had chosen such a life. There was no overwhelming financial need, nor has there been any suggestion of problems in her family background. Her mother, Christine, is a nursery nurse who was concerned for her daughter's welfare. At school Lucy continued to do well enough to gain a clutch of GCSE passes, though she was unaware of this; the results were published after her death in August last year.
In fact, Lucy's year tutor, Pamela Marsh, a teacher at Great Wyrley School, near Cannock, Staffordshire, was glowing both about her former pupil's abilities as a student and her behaviour. Ms Marsh said in a statement, which was read out in court: "I was completely shocked when I read about her ... Of all the pupils, I did not expect her to get involved in what the papers were saying she was doing. She gave no signs or intimation that she would get involved in that kind of thing."
It appears that the reason for Lucy's slide into the twilight was that her fertile mind became fired by a powerful and widely-acclaimed television drama. Lucy told both her schoolfriend and a 15-year-old mate on the street that it was the ITV series Band of Gold, which depicted life on the streets for vice girls in Bradford, that had propelled her into street life.
The schoolfriend, also 16, told the court that Lucy had begun keeping bad company, smoking cannabis and sniffing lighter fuel. Then, in April last year, she announced that she had become a prostitute.
"She told me she had thought about trying to do it after watching Band of Gold. She used to watch that a lot and thought it would be a good idea," explained the friend.
Just quite what she saw in the programme to attract her to such a squalid life has not yet been explained. But she apparently took to the dark side of her double life with all the gusto she had previously applied - and still did - to her school studies.
Her schoolfriend, who disapproved of the other girl's lifestyle and admitted that she had gone "completely off the rails", described how, in between customers, Lucy would call her from phone boxes in the red light district of Walsall.
Another witness, a 15-year-old fellow prostitute, described Lucy's almost meticulous preparations for her evening "job" in the Caldmore area of the town. The girl, a resident at a children's home at the time of Lucy's death, told the court her friend always wore the same blue velvet trousers, cream top and wedge shoes when she was working on the streets. She would call round to the children's home with the clothes hidden in a carrier bag, before getting changed and setting off for the red-light area.
The girl explained: "We heard about Caldmore being an area for prostitutes, so one day we caught a bus there."
Lucy, who bleached her brown hair blonde and had a tattoo with the name Bob, also had a pimp, a young man called Pete. It seems that she only ever worked in Walsall, and even had her own "patch", outside the Dog & Partridge pub, working there most evenings.
"Lucy would go with anyone, anywhere, whereas I had my special places," said the friend.
The 15-year-old said she would use supermarket car parks to entertain customers, adding: "I suppose I was more careful about things."
Though the court heard that her teachers and most pupils were fooled by Lucy's double life, her secret was suspected by someone and passed on to her family. Susan Whiting, a social worker at the children's home where Lucy visited her friend and colleague, said she became aware in March 1996 that the girl was becoming embroiled in prostitution. Ms Whiting told the police in a statement that she had informed Lucy's parents, as she was concerned for her welfare.
In a statement read to the court, Lucy's mother spoke of the changes she had noticed in her only daughter in the months before she died. "Since about March Lucy had got into the habit of staying out very late, and the last couple of weeks had been worse. I thought she lied to us about where she had been."
The statement added: "Once I saw her in her room eating a sandwich at 1am, but I didn't bother asking her where she had been because she would only lie."
Her mother also explained how her daughter had changed her appearance. "Lucy's natural hair colour was a mousy brown, but on 3 August 1996 she had dyed it blonde with ginger streaks. It looked a mess, so she went to have it toned down. This made her hair strawberry blonde."
That was how the girl looked in August last year, when her mother saw her for the last time.
When she failed to return to their home in Cherrington Drive, Great Wyrley, the family reported her missing to the police.
Her decomposed body was found dumped on wasteground behind a Birmingham nightclub five days later. She had died from a large dose of heroin, 80 per cent pure, which the Crown has suggested the two men may have given her in order to "test" its strength and then sat back and watched her die.
The prosecution has alleged that the pair picked up Lucy from her usual haunt outside the Dog & Partridge in August last year, and that she had been in search of cannabis. Despite the future grimly plotted in her "Life Plan", she was still, it seems, only on soft drugs, and not into the heroin that was to kill her.
Probably the last person close to her to see her alive was her best friend from school, who told the court they both shared a taxi to Walsall on the day of her death. "She seemed happy, with no worries, and talked about a holiday she was going on at the weekend."
The holiday, like the rest of her sad Life Plan, never came.