Throughout his childhood and adult life, Roy Whiting never stood out from the crowd. Even when he excelled at his favourite hobby of banger racing he attracted little attention and earned the reputation of being shy and introverted.
Born in January 1959, Whiting found school difficult and left early to take up a string of manual jobs. He first attended Jordans school in Crawley, West Sussex, and then nearby Ifield community college. Former schoolmate Christine Blything remembers Whiting from Jordans.
"He was very quiet and had few friends but he never got up to anything," she said.
"He was a bit of a loner. When he was jailed for snatching the young girl in Crawley I was very shocked. I could not believe it. At the time I did not think he could have done the first crime so as for the second, who knows?"
Whiting had previously been sentenced to four years in jail for abducting and indecently assaulting a nine-year-old girl in June 1995.
When he was 17, Whiting's mother Pamela left the family home in the Langley Green area of Crawley, where he had grown up with his brother and sister. Whiting continued to live with his father but kept in contact with his mother, now Mrs Green.
Eventually Whiting trained as a mechanic and landed a job for a firm in Crawley, a new town in the shadow of Gatwick airport, before breaking away to work on his own. At the same time he developed a keen interest in banger racing, which in the eighties attracted a huge following.
He built his own car and earned a regular slot driving for a team called the Gatwick Flyers at the Smallfield raceway near Crawley. He even had his own driver identity, becoming known as the Flying Fish.
In 1984, Whiting met his future wife. She worked as a petrol pump attendant and became friendly with Whiting when he visited the garage to fill up his car. The pair started a relationship and, two years later in June 1986, they married.
Whiting and his wife continued to live in the Crawley area but their happiness together was short-lived. She began to tire of his obsession with banger racing, and tensions grew when Whiting's business started to fail.
Finally the marriage fell apart and in March 1987, even though the couple were expecting their first child in July of that year, Whiting walked out. The couple divorced in 1990.
His ex-wife, who has asked not to be named, said: "I was the only one bringing in a regular wage and we were always having arguments about it.
"There was never any chance of us getting back together, there was too much water under the bridge. I didn't even know where he was living."
Whiting remained in Crawley after his marriage crumbled and, unbeknown to those around him, began to develop paedophile tendencies which culminated in the horrifying sex attack on his first victim. The offence shared a number of similarities with his attack on Sarah.
During his 1995 court appearance, Whiting's mother was asked to build a profile of her son. She described a Walter Mitty character, who created plans in his own mind which had no chance of coming to fruition and which bore no resemblance to reality.
Probation officers branded Whiting a "dangerous paedophile" and placed him under close watch from November 1997 to March 1998, seeing him once a week. But he then slipped back into obscurity until July last year.
After his release from jail, Whiting moved to St Augustine's Road, Littlehampton, where his reputation of being a loner continued. Neighbours spoke of him being polite but introverted, someone who occasionally helped out but who generally "kept himself to himself".
He worked as an odd-job builder and among places he landed employment was the small village of Kingston, near Littlehampton, in the street behind where Sarah Payne's grandparents lived.
Among those who employed him was builder Terence Heath. Like most others, Mr Heath had no knowledge of Whiting's criminal past.
Mr Heath, who told the murder trial jury that Whiting had dramatically changed his appearance in the days after Sarah was snatched, said: "Whiting was very much an outcast.
"He was very quiet. Usually no one is quiet on a building site. He was a very scruffy individual but he used to get on with his work."
Mr Heath said he had heard from a friend about Whiting's previous conviction. "When I heard what he had done before I was gutted to think I had worked with someone like that. I can't describe how I felt."
In the end, it was Whiting's paedophile past that made him a prime suspect from the outset of the huge hunt for Sarah's abductor.
In the hours after Sarah disappeared, a list of five sex offenders living in the immediate area was drawn by the police inspector on call. Whiting's name was at the top. Whiting was the first man to sign the Sex Offenders' Register in Sussex in 1997 on his release from jail.
Officers visited him at his seaside flat in Littlehampton at 4pm on the day after Sarah was snatched. Whiting was out. Police then visited others on the list but returned to Whiting's untidy first floor flat in St Augustine's Road around five hours later.
This time he was in and gave officers, who had already noticed a white van outside the flat, an account of his movements on the previous day.
The officers left after more than an hour, but, unknown to Whiting, undercover police remained outside the building. Shortly after the officers left, Whiting emerged and went to his van. He was confronted by police.
Detective Constable Steve Wagstaff was among those who spoke with Whiting. He said: "He was extremely nervous. He was visibly shaking, so much so that he actually had problems switching off the engine. He was sweating."
The next day Whiting gave his first police interview, where he opted to remain silent about Sarah's disappearance or his movements on the previous days.
Whiting was bailed, and returned to his home town of Crawley. But rather than going back to his father, he lived rough in a tent in a field in the town.
On Tuesday February 6 2001, police officers arrested Whiting at a Kent prison, where he had been serving 22 months' imprisonment for stealing a car and dangerous driving.
Whiting had been jailed for trying to ram two police cars when he realised officers were following him in the early hours of July 23 2000.
Police took him to Bognor police station for final questioning. He was charged with kidnapping and murdering Sarah. Among those to sit in on the interviews was Detective Inspector Martyn Underhill, who was second in command of the investigation.
He said: "Whiting came across as being very arrogant, almost bored with it all. He was an isolated individual, a classic 'Billy no-mates' type of person."