As he was led to the scene of his eventual death 17-year-old Simon Everitt was heard to whisper a prayer. One of his killers, Jimi-Lee Stewart, later recalled how he had been “asking God and Jesus to save him”.

Prosecutor Karim Khalil later observed that it was clear to Simon, even at this point, that he was going to die.

His killers were carrying rope and petrol, had ignored his cries for help and had intercepted his attempt to dial for an ambulance after he was given a beating. But it is doubtful, even after all this, that he was able to imagine the horrendous torture that lay ahead.

The killing centred around Fiona Statham, who was 19 at the time of Simon's disappearance in June last year.

Even in the relatively sober terms used by barristers at Norwich Crown Court, the mother-of-one had been “playing off” Simon, Stewart and Jonathan Clarke.

The series of relationships is far too complicated to untangle. But the crucial point came on June 7 when, after six-months of on/off and sometimes consecutive trysts, Miss Statham ended things with Stewart.

She wanted to return to Simon - who she told the court she loved - and although she did not say as much in her brief text message to Stewart, he quickly guessed her reasons.

The previous day Maria Chandler had encouraged Simon, Stewart and Clarke to meet to discuss their differences. This was doomed to failure and ended in Clarke being arrested for attacking Simon with a baseball bat - an omen for the following day's events.

Under the pretence that a female friend wanted to meet Simon, Stewart lured him to a lay-by at Corton. The pair rode their together on bikes and throughout the journey Stewart maintained the pretence of friendship. But it was there that the nightmare began to unfold.

Clarke set about him with a homemade cosh - three thick pieces of wire wrapped in tape.

It was a savage beating but Simon managed to run away. He was unable to escape though as Stewart caught up with him.

As Stewart confronted him, Simon was speaking to the ambulance service having made a 999 call. Stewart took control of the conversation, saying he would call back when he had established their location. He never called back.

Stewart claimed he had only ever intended to scare Simon and leave him to be discovered by a passerby. Chandler said she was forced to go along with the plot. Both painted Clarke as the prime mover.

There is little doubt that the method used came from Clarke - he was inspired by a scene in horror movie Severance in which a woman is killed in almost identical circumstances. After watching the clip he told a friend: “Wouldn't it be wicked to actually do that to somebody in real life.”

But he was not the only one capable of imagining extreme cruelty. Stewart's original plan had been to tie Simon to the rear of a car and drag him around the streets of Yarmouth. He told jurors that he expected this would have caused “a few cuts and bruises” but was undoubtedly aware that the consequences would be far more serious.

Clarke relied on an extraordinary defence - insisting that although he was capable of “ferocious violence” he would have used an entirely different form of torture. He claimed he was not involved at all and spent the night on Yarmouth beach. “If I'd have done it I'd have cut of a finger or a toe and dismembered him bit by bit,” he said.

What actually happened to Simon is now depressingly ingrained on the public consciousness: he was tied to a tree, interrogated about his relationship with Fiona, doused in petrol and then set alight.

Forensic examination later showed the flames he burnt through the rope which bound him to the tree - perhaps giving a still conscious Simon the false hope of survival. But he fell on his side and burnt to death on the forest floor. The only consolation is that he may have past out from the fumes long before the fire burnt out.

Later Clarke, possibly accompanied by one or more of his accomplices, returned to the scene to dispose of the body.

Simon's final resting place was in a nearby swamp-like ditch. When police found him he was almost submerged. His remains were so badly decomposed that it took some time to establish that they were indeed human, let alone confirm the identity of that person.

It was a statement from Stewart's mother which eventually led to the trio being arrested. But rumours of what had happened were already rife in Yarmouth.

None of the three were able to keep quiet: Chandler told her partner and, after her arrest, a neighbour; Stewart confessed to his mother and her partner; Clarke bragged openly about it and threatened to do the same to others who upset him.

In police interviews each gave confused and contradictory accounts.

This amounted to little more than mudslinging, each trying to place the blame on one another.

But ultimately each was equally culpable. None showed remorse.

Perhaps the most shocking detail of this case is that three people could collude in such depravity, without a single one questioning their conscience.