THE alleged blackmail plot against a member of the royal family began in a flat not far from Buckingham Palace occupied by a young royal aide. It is there, according to the aide, that a party took place attended by a junior royal.

According to a CD-rom, part heard by The Sunday Times, the aide claims: “We were all pissed, on the kitchen floor. We were on the kitchen floor, [the royal] runs to get the drinks and he says ‘dear, dear’.” He described a sexual act: “We were lying on the kitchen floor. [The royal] unzipped my trousers . . .”

The junior royal is said to have been interviewed by detectives Last week’s Sunday Times story about the claims in two disks, comprised of 16 audio and 24 videotapes. Police are said to be “fully satisfied” that the allegations are untrue.

Although neither the royal nor the aide can be named, the man who brought the claims to light, the alleged blackmailer, can be identified. He is Ian Strachan, 30, who was born into a modest background in Aberdeen as Paul Adalsteinson.

He was educated at Mile End primary and Aberdeen grammar school. One former classmate at the latter said: “He wasn’t a popular boy because he became a self-centred poser who loved himself.

“It was an incredible transformation virtually overnight when he turned 16. Gone was the quiet, loner-type guy. Instead he was this loud, confident guy with slicked back hair and shades strutting about like a ladies’ man who owned the city.”

Strachan ended up living with his mother in a penthouse apartment in Imperial Wharf, a development of luxury flats in Chelsea. He is well known on the London nightclub circuit and got to know the royal aide involved in the blackmail case. Strachan recorded the aide making the allegations initially at the behest of a tabloid newspaper.

However, according to legal sources, the aide made the allegations while under the influence of cocaine. He may also have been trying to impress Strachan, to whom he was apparently attracted.

The alleged blackmail bid began on August 2 when a man giving only his first name called the office of the junior royal. He said he was aware that another man who worked on the royal’s staff had been in possession of an envelope containing cocaine.

The caller then claimed he had a video in which the aide engaged in oral sex with the royal. The caller asked the royal to contact him and left a number.

During subsequent discussions a caller – there was more than one – claimed the tapes showed the royal aide snorting cocaine. At some point, it is alleged, one of the callers asked for £50,000 in exchange for not releasing the tape, although this point is hotly disputed.

The royal is then said to have called in Scotland Yard. A detective was attached to the royal staff. Using the name Paul Butler, he took over negotiations. The callers agreed to meet Butler in a private room at the Park Lane Hilton in Mayfair.

The meeting was secretly videoed by officers in an adjacent room. They moved in to handcuff Strachan and another man called Sean McGuigan once part of the tape had been shown. Strachan claims: “We went into the room, shook hands with Butler, who pulled out a laptop and I started playing the tape . . .

“Eventually he said that he had seen enough and wanted to talk about money. He also [asked] were these all the copies of the tape. He brought up the conversation about money.”

Strachan’s legal adviser is Giovanni di Stefano, who has represented several notorious clients including Saddam Hussein, Nicholas van Hoogstaten, the controversial landlord, and Kenneth Noye, the road rage killer. Di Stefano said last week that his client denied blackmail.

“This boy has done everything possible to protect the royal family. He only wanted to attack a man who behaved in an improper manner,” he said.

Strachan claims it was the royal’s legal adviser who first suggested that money changed hands – after learning the media had offered Strachan cash for the tapes. The full trial is expected to start at the Old Bailey next year.

Additional reporting: Anna Mikhailova

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