The story was fantastical but horrifying, told by a man known only as “Nick.”

When he was a boy, Nick told police and the press, he was “handed over” by his abusive stepfather to a powerful group of men who repeatedly raped, tortured and traumatized him and countless other boys for life. Some of the most powerful men in British Parliament and the military — including the former prime minister and chief of the armed forces — were part of the ominous gang, operating from 1975 to 1984, Nick remembered. How could he forget? he said.

They would send cars to pick up Nick and the other boys at random locations — the train station, a street corner — and take them to luxurious apartments and hotels all over London. There, one by one, or sometimes all at once, the boys would endure unthinkable sexual abuse and torture, sometimes so brutal that the beatings resulted in young boys’ deaths, Nick said. He said he witnessed the murders of three boys, two of whom he claimed were killed for sexual pleasure by a Conservative member of Parliament at the time.

The lurid tale shocked the nation, launching an enormous investigation by the United Kingdom’s largest police agency. In December 2014, a homicide detective for the Metropolitan Police Service described Nick’s allegations as “credible and true” and begged any other victims to come forward. Nick appealed to the public too, appearing in videotaped interviews as a black silhouette with a disguised voice, saying to the other abused boys he hoped were listening, “It’s important that they come forward too. . . . It’s something that stays with you forever.”

But month after month — as the sensational allegations remained under investigation by police, as the accused high-ranking former government officials watched their reputations disintegrate into scandalous tabloid fare — no other boys came forward. In fact, nobody did.

For years, the public would have no idea who “Nick” was — until finally, after a 12-week trial that ended this week, the full picture has emerged. Nick was Carl Beech, a fabulist who invented the entire story, a jury concluded on Monday — and a pedophile masquerading as a child sex abuse advocate and charity volunteer, managing to fool police and captivate Britain.

Beech, a former pediatric nurse, was convicted Monday of 12 counts of perverting the course of justice and one count of fraud, for collecting 22,000 pounds (more than $27,000) after he also falsely claimed to be a victim of one of Britain’s most notorious sex abusers, an entertainer named Jimmy Savile, BBC reported. He faces sentencing on Friday. Beech’s wild allegations of murder and the rape and torture of children cost the Metropolitan Police Service 2 million pounds ($2.5 million) for the 16-month investigation, as they raided innocent and elderly former government officials’ homes in search of sordid evidence that did not exist.

At the end, all police found was a hoard of child porn on Beech’s own electronic devices, the Guardian reported.

On Monday, Harvey Proctor, the Conservative member of Parliament who was accused of killing two young boys, called the case a “truly disgraceful chapter in Metropolitan Police history.” Many of the other high-ranking military or government figures were in their 80s or 90s at the time they were accused, making Proctor one of the few who is still alive.

One, Leon Brittan, Britain’s former home secretary, died of cancer in 2015 before he could learn his name had been cleared. Another, Lord Edwin Bramall, a World War II war hero and Britain’s former chief of the armed forces, is now 95 — but his wife of 60 years died in 2015 before she could learn he was innocent, the BBC reported. Proctor said he saw it as his duty to fight for those who no longer had a voice.

“In these precious last years of my life, I know I can never regain what has been taken from me through Mr. Carl Stephen Beech’s mendacious activities, and the consequence of the rogue, malicious and apparently homophobic Metropolitan Police Service’s investigation,” said the 72-year-old Proctor, who is gay. “I have a voice and I will continue to use it, and whatever is left in my future, I will do what I believe to be right.”

At first, as Nick started sharing his story in British tabloids in 2014, the details remained mysterious, the high-ranking powerful figures unknown. Not even Nick revealed their identities in anonymous interviews with tabloids and even respected news outlets such as the BBC.

But once police began raiding the ex-military officers’ and Parliament members’ homes in 2015, their identities were revealed — and the scandal exploded. Raids were carried out at the homes of Proctor, Bramall and Brittan. Several others, including Sir Edward Heath, Britain’s former prime minister, were among the accused. Heath died of pneumonia in 2005.

All the while, Beech was hoarding as many as 350 indecent images of children, dozens of which were classified as the most serious types. He also recorded a surreptitious video of a teenage boy urinating, as the Guardian reported.

The child advocacy charity he was working for had no idea — no one would for years. He worked as a volunteer for the National Society for the Prevention of Cruelty to Children from 2012 to 2015, giving speeches to classrooms full of kids for the charity’s “Speak Out Stay Safe” campaign, the Guardian reported. (The charity said it never received any complaints about Beech from children, according to the newspaper.)

In 2015, as the Operation Midland raids were unfolding, the 51-year-old also started a social media campaign for child sex abuse survivors, collecting their stories and photos on Twitter and publishing them on a blog. Another charity supporting child sex abuse survivors was impressed with Beech’s idea. The Southmead Project turned it into a special exhibit commemorating victims at London’s City Hall, called the Wall of Silence.

“I’m on the wall. As a survivor, I’m devastated,” Mike Peirce, the charity’s founder, told the Guardian on Monday following Beech’s conviction. “It has triggered trauma and my guess is it would have triggered the trauma with so many other people, their despair.”

Back in 2015, however, nobody knew that “Nick” was Carl Beech. Nobody would know until December 2018.

Proctor, infuriated that the press and the police were trusting the story of one anonymous man, called a now-famous news conference in August of 2015 to ask police to either arrest him for murder and let him prove his innocence in a court of law — or to unveil Nick’s identity and prosecute him for the false claims.

He stood by himself at a lectern, reading aloud and in third person from a police report that detailed the incredible allegations waged against him. With a straight face, Proctor said: Nick told police that Proctor raped him when he was just 12 years old. That Proctor choked a boy to death while brutally raping him on a table. That Proctor joined a group of men in beating one boy to death after raping him. Nick said that, one day, while he was walking down the street, a car mowed down the friend who was walking with him, because, as Proctor read, “he was warned not to have friends in the future.”

Finally, Proctor looked up, hoping to find a face of incredulity on the reporters in the room.

”I am completely innocent of all these allegations,” he said. “I am a homosexual. I am not a murderer. I am not a pedophile.”

Several months later, the Metropolitan Police dropped the investigation. They apologized to then-92-year-old Bramall and to Proctor for the raids — a futile gesture in Proctor’s view. He lost his home and his job after the raid, the Telegraph reported.

From then on, the scandal became how a prestigious police force was fooled into lending credibility to a single man’s horrific story of torturous abuse and murder by politicians without a single witness to back up his decades-old claims, as a judge found in a 68-page report investigating the fiasco in 2016.

A separate agency, the Northumbria Police, took over the investigation into Beech, finding the child porn in December 2016. Beech was formally charged in June 2017 with four counts of making indecent photographs of children, one count of possessing indecent images of children and one count of voyeurism. Because Beech’s identity was kept secret until only recently, the public was unaware of these charges until his trial on fabricating the pedophile ring.

When he was charged with possessing child porn, the Guardian reported, he at first tried to frame his teenage son, pleading not guilty. He briefly went on the run in Sweden before returning for his trial October, where he changed his plea to guilty.

The court asked him why he lied.

“Because I was totally ashamed of what I had done,” he said, according to the Guardian. “I couldn’t admit it to myself. I was in denial.”

Correction: A previous version of this report incorrectly stated the amount of money Beech fraudulently collected, as well as the total cost of the police investigation into his claims. He collected 22,000 pounds, and the cost of the investigation was 2 million pounds (roughly $2.5 million).

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