Two men were each jailed for five years today after being found guilty of a £50,000 gay sex blackmail plot against an unnamed royal.

Ian Strachan and Sean McGuigan demanded the money for a set of recordings featuring “scandalous” remarks by a royal employee, known only as witness D.

Among the claims were that the married royal, witness A, performed a sex act on witness D at a party.

Strachan and McGuigan used the tapes to demand money from A after trying but failing to sell them to newspapers for up to £60,000.

They were arrested in September after a sting operation at a London hotel by undercover police officers posing as other royal assistants.

Strachan, 31, of Fulham, south-west London, and McGuigan, 41, of Battersea, south London, were facing jail today after being found guilty by an Old Bailey jury of demanding money with menaces.

The verdict followed a police investigation and three-week trial thought to have cost at least £1 million.

Mark Ellison QC, prosecuting, said it was a “classic example of blackmail”.

The court heard that Strachan was a “Walter Mitty” type fantasist who liked to claim he was a friend of royals and lived a champagne lifestyle.

But in fact he was a university dropout who owed thousands of pounds to a royal employee, known as witness D, and lived with his mother.

Strachan claimed in court to have met the royal, A, on several occasions and that he never wished to harm him.

Instead, he wanted to expose D as a “predatory homosexual” who drugged people to have sex with them, he said.

While he had no serious convictions, Strachan was investigated in 2004 over an accusation that he threatened a man by phone and text message.

Texts allegedly included “you will end up with a bullet in the back of your head” and “you will end up in the bottom of the river”.

McGuigan, a recovering alcoholic, made contact with A’s representatives in July last year and was present as the tapes were played to an undercover officer posing as a royal aide, in a meeting shortly before both men were arrested.

Ronald Thwaites QC, defending McGuigan, said he was “someone who fantasises in a compulsive way to the extent that you don’t know which bits are true or false”.

A married member of the Royal Family, witness A cannot be named and did not give evidence in court. But he told police claims about him were “spurious and without foundation”.

The lurid allegation at the centre of the trial was that he performed a sex act on an employee, witness D, at a party, after being egged on by a Stringfellows stripper called Cindy. It was also suggested that he had taken drugs.

Witness A, who was on holiday in France when he was told by a friend about the claims, said he would do “whatever it takes” to protect his family from the alleged blackmailers.

The jury only took four and a half hours to reach a unanimous verdict, despite the judge telling them not to “rush” into a decision.

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