The extensive search for Shannon cost the police £2.5m
On a Tuesday afternoon in February the pupils of Westmoor Primary School in Dewsbury headed home after lessons as normal.
But what happened in those moments beyond the busy school gates led to one of the most extraordinary hunts for a missing person in recent years.
One of the children from the school, a timid nine-year-old called Shannon Matthews, never got home and has not been back since.
Police first became aware that something was wrong when her mother, 32-year-old Karen Matthews, made a 999 call at about 7.30 that evening.
She told the operator she had already checked with family and friends but she could not find Shannon.
The early stages of the biggest police investigation in the county since the search for the Yorkshire Ripper began that evening.
What followed was the coldest night of the year and a police news conference the following afternoon outside the school gates, with officers trying to make people aware of who Shannon was and what she looked like.
Had Shannon run away? Had somebody taken her? Was she dead or alive?
Karen Matthews came out of her home on the Wednesday evening sobbing for the safe return of her daughter.
"Shannon, if you're out there please come home, we love you to bits, we miss you so much. Please return her home safe," she said.
She appeared to be going through a terrible ordeal. Desperate, frantic and clueless about the whereabouts of her vulnerable daughter.
But Philip Bretton, who lived in the same street, later said he had seen Matthews laughing a few hours after Shannon had gone missing.
Karen Matthews' motivation for what happened remains unclear
"I knew straight away, as soon as I saw her... there was more than met the eye," he said.
"And I even turned round and said to a number of people that I wasn't going to go out and look for her, because they knew something.
"She wouldn't walk up the street laughing and joking about if her kid was missing.
"You'd go out and search, you wouldn't be getting drunk at night would you?"
CCTV pictures of Shannon just minutes before she disappeared were released but they yielded nothing.
Police underwater search teams smashed through ice-covered ponds.
Houses were searched, roadblocks were set up and thousands of wheelie bins were emptied looking for clues.
Uniformed officers, mounted police and plainclothes detectives were on the ground in Dewsbury turning the place over. It was not unusual to see 300 officers per day putting a small area of a small town under the microscope.
Within a few days the nation knew who Shannon was, her picture appeared everywhere. Police repeatedly stated they believed the answer to her whereabouts was local.
The officer leading the investigation, Detective Superintendent Andy Brennan, became increasingly concerned, stating that Shannon could have "fallen into the wrong hands".
Just before Mother's Day, Karen Matthews made another appeal.
Sitting in Dewsbury Police station, cuddling a toy belonging to her daughter, she made what turned out to be a very perceptive statement.
"Well, I think that somebody out there who knows Shannon and probably knows me as well [is responsible]. I just want her home safe," she said.
Then, 24 days after the little girl had disappeared and when many people had given up hope of finding her alive, police raided a first-floor flat barely a mile from where Shannon had last been seen.
It belonged to a man called Michael Donovan who was an uncle of Shannon's mother's partner at the time. Detectives had gone in after a tip-off from June Batley who lived in the flat below.
She said: "We just told the detectives we'd heard a little one upstairs and they just went then and said "we will be back". Then all these policeman arrived in their vehicles and came and battered the door down.
"They went inside and found Michael and little Shannon in the bed. We saw them bring Shannon out and we just asked the detectives is that Shannon? And he said "yes" and she looked fine. A bit nervous, but she looked fine. Then they dragged Michael out and took him away."
Shannon was found hidden in the drawer of a divan bed. Donovan, a small weak-looking 40-year-old man, was in another drawer. He had kept Shannon in his flat since she disappeared.
After officers led him outside, Donovan told them: "Get Karen down here. We had a plan. We're sharing the money - £50,000."
His former wife Sue Bird has spoken exclusively to the BBC about his actions.
"If he did it on his own, how did he expect to get away with it? And what would he have done to cover his tracks?" she said.
"If he is that unstable to keep a little girl in his flat when virtually the whole country is out looking for her, how on earth does he expect to get away with that? That scared me. Thank God they found her when they did."
Karen took the biggest intake of breath I have ever heard in my life and said, 'Yes, that's right'
Det Con Christine Freeman
However, Donovan was not working alone. His accomplice was Shannon's own mother.
The 999 call, the appeals and the tears were all an act by Karen Matthews. She had known, or at least had an inkling, where her daughter was from the moment she went "missing" and said nothing about Donovan.
While police spent £2.5m searching for Shannon.
The day after he was arrested, Donovan told officers that weeks before Shannon went missing Karen had asked him for "a big favour".
They had arranged to meet in a cafe in Dewsbury town centre where Karen had told him to look after Shannon and there "would be some money in it" for him, he said.
Donovan added Matthews had threatened to get three lads on to him if he refused and that he had recognised one of the names as that of a violent criminal and had eventually said: "OK, I'll do it."
On the day Shannon went missing Matthews had waved at him to indicate he should wait at the end of her road, Donovan said.
Twenty minutes later, he told officers, Shannon had come up to his car and said: "Hi Mick, my mum says we're going to a fair tonight." And with that Shannon was gone.
She said the reward had gone up to £35,000 - she told me if it went up to £50,000 she would ring me again
At the time the nine-year-old was found, Karen Matthew's involvement was yet to emerge.
So the day afterwards, Karen happily posed for photographs outside the family home, playing the emotionally drained but relieved mother.
But days later she blurted out the truth to friends in a car being driven by a police officer. She was immediately arrested.
Natalie Brown put it to Matthews that she had wanted to leave her partner and had asked Donovan if she could stay with him - but on the day he had picked up Shannon, she had lost her nerve and found herself reporting her daughter as missing to cover her back.
Det Con Christine Freeman said: "Karen took the biggest intake of breath I have ever heard in my life and said, 'Yes, that's right'." Matthews was immediately arrested.
Anger and betrayal
In the community of Dewsbury Moor where most people at one time or another turned out to look for Shannon there is still a feeling of anger and betrayal. Petra Jamieson, a neighbour of Karen Matthews, sums up the feelings of many.
"I feel sick and shocked that we were all fooled. Even the children got fooled as well and some of the kids were scared that it would be them next time," she said.
Donovan said the plan had been to release Shannon in Dewsbury Market, for him to pretend to find her and claim the reward money.
During the second week of the search, he added, Karen had called him.
"She said the reward had gone up to £35,000. She told me if it went up to £50,000 she would ring me again," he said.
The fact that she kept quiet and he kept a frightened and confused nine-year-old-girl he barely knew in his flat for days will lead to both of them serving lengthy jail sentences for kidnap.