A month before Hannah Deterville was to be confirmed at her Catholic church, the schoolgirl was abducted and stabbed 20 times in the neck and face for no apparent reason.
Three weeks after she went missing, her body was found, partially hidden, in woodlands at a popular beauty spot on the western outskirts of London.
Forensic examination quickly showed the 15-year-old had not been sexually assaulted, nor had she been robbed of her jewellery and money.
Today, the first anniversary of the recovery of Hannah's body, police still have no explanation for her death.
The case is a mystery which nags at the professional pride of some of the most experienced detectives in the Metropolitan Police force.
It also provides an insight into the parlous relationship between the Met and black people in London, in the wake of the shocking evidence from the Stephen Lawrence inquiry.
Hannah's mother June told the Independent on Sunday that several people had suggested possible motives but refused to speak to police.
"It's like there is a taboo with the police, especially in the light of Stephen Lawrence," she said. "As much as [these people] would like to help, they feel they cannot be involved."
For Superintendent David Niccol, heading the murder inquiry, called Operation Maidstone, the lack of information is frustrating.
"We cannot find a damn motive at all," he said. "What makes someone so livid with her to stab her so many times and continue stabbing her after death?"
Supt Niccol said the case was "extremely unusual", adding: "The effort that has gone into trying to hide her body, the severity of the wounds [and] the lack of any motive whatsoever makes it very unusual."
The scenario of a psychopathic "travelling salesman" has not been wholly ruled out. But Supt Niccol said the killer was probably someone from the world Hannah inhabited, close to the bustling Harrow Road that links the west London districts of Paddington and Harlesden.
Her mother is a well-known local figure. She is a director of the Yaa Asantewaa community centre, and helps to organise floats for the annual Notting Hill Carnival. Hannah was a carnival regular, so well-recognised on the Harrow Road that she was on first-name terms with many shopkeepers.
But on the evening of 2 January last year, she became strangely invisible. Her mother said goodbye to her around 7pm and she was never seen alive again.
Hannah, in orange jeans, a grey bomber jacket and red Reebok trainers, was streetwise enough not to get into the car of a stranger, and police believe she probably accepted a lift from someone she knew.
Her body was found close to a golf course at Horsenden Hill in Greenford, an area popular with walkers and dog owners but also frequented by cruising gays. Police were alerted after an anonymous call to the Gay and Lesbian Switchboard, but they have so far failed to find the caller.
Detectives believe Hannah was killed within 12 hours of being abducted and that her body was kept for many days before being dumped. At least two people would have been needed to carry the body.
Her mother said Hannah, a "fun girl" who liked athletics and drama, was studying for her GCSE exams at St Thomas More Catholic school in Chelsea.
But Mrs Deterville said even some of Hannah's best friends seemed reluctant to try to throw light on what happened. The Deterville family also feel the police failed to take Hannah's disappearance seriously at first.
"It was only after two weeks that the police reckoned she was vulnerable," said Mrs Deterville. "She was vulnerable from the beginning. It was the third week before they sent a constable to the house but by then it was too little, too late. We had already done what needed to be done, contacting the media and putting up posters."
In September, after nine months of frustration, new forensic experts re-examined what evidence there was. But although five people have been arrested at various stages, none has been charged.
In the wake of the Lawrence fiasco, the Met is pulling out all the stops to show that a victim's race has no bearing on the thoroughness of an investigation.
Detective Inspector Brian Pender said: "Both myself and my team of officers are committed to seeking justice for young Hannah and trying to bring a degree of comfort to June and her family. This is probably the most horrific murder investigation I have been involved in."
But the Lawrence findings appear to have severed some of the last threads of communication between the police and a community which has long suspected that black deaths were treated as low priority.
June Deterville, who has two other children, appealed for people to put aside their mistrust and help the police.
"I want the police to get this killer," she said. "He or she might do this again."
Operation Maidstone team: 0181-358 1875.Reuse content