In July 1981 a young boy disappeared from Barnes, south-west London, as he made his way home from the crowds gathered to watch the wedding procession of Prince Charles and Diana Spencer.
Months later, a man called the child's father, claiming to be a prostitute and saying he had information about the young boy's disappearance.
"He told me he believed (my son) may have been taken by pedophiles in the Elm Guest House near Barnes Common. He said there were very highly placed people there. He talked about judges and politicians who were abusing little boys," the father later told the Telegraph.
Although he recorded the conversation and passed it to the police, it was apparently never investigated.
"They just pooh-poohed it and I never heard anything about the tape again. The whole thing went cold," said the father. "At that time I trusted the police. But when nothing happened, I became confused and concerned. Now it is clear to me that there has been a huge cover up."
In February 1982, parts of the boy's skeleton were found in a West Sussex woodland.
Last week, a judge was appointed to lead an inquiry into claims that senior figures in British public life participated in a violent pedophile ring, and that they were protected by an establishment cover-up spanning more than three decades.
But the new appointee is not the first. The claims reach so far into the heart of the British establishment that two senior legal figures appointed to lead the inquiry were compelled to resign, after it became clear they were linked to people it would need to investigate.
Home Secretary Theresa May eventually decided to look abroad, picking Justice Lowell Goddard, who has a record of investigating police mishandling of child abuse cases in her native New Zealand.
May said Goddard is "as removed as possible from the organizations and institutions that might become the focus of the inquiry."
Elm House is one of at least three locations where witnesses say they were abused by politicians and other senior establishment figures during the late 70s and early 80s. Another is a block of flats on Dolphin Square in Pimlico, West London. At one time, it was home to at least 80 members of parliament (MPs).
Investigative website Exaro, which has taken a lead in reporting on the scandal, interviewed three men who say they were sexually abused there as children by MPs, and who separately identified a former Conservative cabinet minister as having been present at the time.
One of the men claimed to have witnessed three child murders, one in front of the former minister, during the "abuse parties." A senior police officer working on the case described the allegations as "credible and true."
Two of the men said that they were brought to the abuse parties by Peter Righton, who advised the government on child care, but secretly ran pro-pedophilia network the Pedophile Information Exchange. He was convicted of child pornography charges in 1992.
In December, Labor MP John Mann handed a dossier to police naming 22 politicians alleged to have been involved in the Westminster pedophile ring, of whom 14 were Conservative. Six of the accused were reportedly still serving parliamentarians.
What did Margaret Thatcher know?
Claims that senior figures in the British establishment had criminally pursued a sexual interest in young children are understood to have reached Margaret Thatcher when she was prime minister — three times. Yet she reportedly did nothing about them.
Between late 1980 and early 1981, Thatcher was presented with a series of notes on the sexual interest in young children of former diplomat and deputy director of MI6, Peter Hayman. Her own annotations, which came to light in January 2015, suggest she did not want to see Hayman named, and that she considered the allegations a "slur."
The file says there was no evidence he had ever acted on his "fantasy," although he has subsequently been identified by a witness as an allegedly active participant in the abuse.
In July 2014, Thatcher's former bodyguard, also a former police detective chief inspector, claimed that he warned the prime minister over allegations that her adviser and confidant Peter Morrison had participated in sex parties with underage boys. She went on to appoint Morrison deputy chairman of the Conservative party in 1986.
Archie Hamilton, then Thatcher's parliamentary private secretary, has subsequently said that in his recollection the allegations only concerned sex parties involving adult men.
Thatcher is also alleged to have ignored a third warning. A former Conservative activist, Anthony Gilberthorpe, claimed last July that he had attended sex parties with top Tory parliamentarians at the 1981 and 1984 Conservative party conferences.
"There were several men walking from one room to another and enjoying sex acts with other naked men, including boys who were clearly only about 15 or 16 years old. I saw Keith Joseph (Thatcher's right-hand man) there and a politician who is now still a serving MP," he said.
He said he'd also been asked to procure "entertainment" for two cabinet ministers at the 1983 conference.
"I was expected to find the youngest and prettiest boys. It was what those men wanted," he said.
Gilberthorpe claims he did as he was asked, returning with "two boys who were aged about 15 and no older."
The party activist says he sent a 40-page dossier to Thatcher in 1989, describing what he had seen. He says he received no response, but was summoned to a meeting with William Hague, now leader of the House of Commons, and a senior civil servant.
According to Gilberthorpe, the civil servant dismissed the claims.
"Why you are writing to the prime minister about these matters is beyond me," Gilberthorpe recalled the civil servant saying at the meeting. Hague, he claimed, said very little.
Detectives, dossiers and D-notices
It wasn't that no one had been aware of the far-reaching allegations at the time, or even that no one had tried to do anything.
In 1982, police raided Elm House. Although as many as 12 boys told police that they had been abused there, no charges of child abuse were brought.
After the raid, the press published two series of articles about the goings-on at Elm House. One 1982 article referred to "the murder of one boy and the disappearance of another."
But several police officers have claimed investigations into prominent pedophiles were shut down.
"It went to Cabinet level," one former detective wrote on an online forum for serving and ex-members of the Metropolitan police, in a discussion to which several officers contributed.
The former editor of the Sunday Mirror has said he was told by police that after Thatcher's adviser Peter Morrison was arrested for molesting children in a public toilet, senior officers ordered the case dropped.
Sometime in the early 1980s, Barbara Castle, a former Labor cabinet minister and then a member of the European Parliament, passed a dossier naming 16 politicians who were allegedly supporters of the Pedophile Information Exchange to Don Hale, at the time editor of the Bury Messenger local newspaper. Last July, Hale claimed that his office had then been raided by Special Branch, who seized the dossier. They issued him with what he says appeared to be a D-notice, an official order not to publish information deemed sensitive to national security. Another local newspaper editor was also issued with a similar notice around the same time.
A spokesperson for the D-notice system told the Guardian: "If Don Hale was 'served' with anything purporting to be a 'D-notice', it was quite obviously a fabrication."
The late Conservative MP Geoffrey Dickens also appears to have realised that something was badly wrong, and by 1984 had compiled a 40-page dossier naming eight well-known figures.
Dickens told his son that the dossier would "blow the lid off" the case, but he chose to give the file to then Home Secretary, Leon Brittan. It has since disappeared, along with 114 other relevant Home Office documents.
Brittan died on January 21, and has since been named by the Mirror as the cabinet minister who, according to the witness cited by Exaro, was present during the killing of a child during an "abuse party" at Dolphin Square.
Senior Conservative politicians praised Brittan and denied the claims. Hague called him a "kind, assiduous, and brilliant man."
The former Home Secretary was buried in an unmarked grave in a discreet ceremony in the last week of January.
Main image: Dolphin Square in Pimlico, London, one of the sites at the center of the abuse claims.
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