Secret files have revealed how a man accused of plotting a Mumbai-style attack had enjoyed a billionaire's lifestyle with "good friends" of the Duke of Cambridge and Prince Harry before his arrest.
The newly released transcripts from Britain's first secret terror trial detail part of Erol Incedal's defence which was heard behind locked doors in the interests of national security.
But the crux of the case against the law student, from south London, remains shrouded in mystery, despite a High Court challenge by the media citing the principle of open justice.
Incedal, 27, was cleared of targeting former prime minister Tony Blair or plotting a Mumbai-style attack following the Old Bailey retrial in April, but was convicted of possessing a document useful for terrorism and jailed for three-and-a-half years.
His friend Mounir Rarmoul-Bouhadjar, also 27 and from London, admitted having the same bomb-making manual on a memory card and was jailed for three years.
The court records relay Incedal's account of high rolling playboy antics in the months before his arrest in October 2013.
They explain how he came to be living in a plush bachelor pad in Paddington with no income apart from a student loan, and why he was driving a Mercedes and wearing a £15,000 designer watch when he was arrested.
The married father-of-two told how he struck up a friendship with fellow Muslim student Ruslan Mamedov in 2007.
Mamedov was a "gofer" for billionaire sons of a minister in Azerbaijan who liked to mingle with celebrities and super rich Russians and Arabs at "very expensive" west London nightclubs and lounges such as Tramp, Mamounia Lounge and Salt, he said.
Defending, Joel Bennathan QC asked Incedal about evidence from a police bug planted in his car which recorded him bragging to Rarmoul-Bouhadjar about having "£20,000 in my pocket".
Incedal explained: "Ruslan, my friend, he had four credit cards.
"Each card he could withdraw about £4,000 to £5,000.
"Because he would be spending that evening partying and drinking he would give me the money to look after.
"He had billionaire friends and he was basically working for them.
"They used to spend £20,000 to £30,000 in clubs every night so he would take out a lot and keep some of it for himself - not telling his boss, obviously.
"He would ask me to look after it in case they looked in his jacket and saw large amounts of money and then I would return it to him the following day."
Asked if he really was carrying £20,000, he said: "I actually wasn't.
"It was 17 or something, but I rounded it up to show off to Mounir and when we went out that evening, I was showing off that I had a lot of money."
Incedal told jurors that Mamedov's billionaire friends knew what he was doing "but for them it was like £5 or £10 so they didn't really care".
Asked who these "fabulously wealthy people " were, he said: "They are sons of a minister in Azerbaijan, good friends with Prince William and Harry."
He went on to describe how his friend would take him and Mounir on spending sprees in Harrods and Selfridges so they would look the part in exclusive bars.
"Me and Mounir we didn't really have expensive clothes so ... before Ruslan started taking us, he would always take us to places like Harrods, Selfridges and buy us expensive clothes to go to these places."
When he was arrested in the Mercedes car Ruslan helped him buy, Incedal said he was "quite kitted out" in a £15,000 diamond Rado watch from Harrods, a £500 Bugo Boss jacket, a £300 pair of shoes, and a Louis Vuitton wallet.
He added: "They are so wealthy, in Hyde Park, near Park Lane, I think it was a roller coaster, like a funfair.
"And Ruslan is scared of heights and stuff.
"So they said to him they would give him 20,000 euros if he went on the roller coaster.
"Other times they will say to him 'if you can chat up this girl, I will give you 10 grand, 20 grand. So it was a joke for them really, money."
Mamedov rented the flat in Sussex Gardens, Paddington, for the billionaires but allowed Incedal to stay there after his marriage broke down and his wife told him to leave the family home in south east London.
The defendant said that although they owned a house near the Royal Albert Hall, a £10 million home in Hampstead and another near Edgware Road, the billionaires needed somewhere central "to party" with women they had picked up.
But the billionaires regularly flew in their private jet to Monaco and elsewhere, so they could use it for their own parties while they were away, he said.
Incedal also gave details about his trip with Rarmoul-Bouhadjar to the Syrian border in Turkey where he learnt about Kalashnikov rifles and met a jihadi called Ahmed who told him to go home and do some "shit".
But Incedal, who has Turkish roots, repeatedly denied that he had actually planned to carry out any sort of terror attack in the United Kingdom.
The vast majority of the trial was heard behind closed doors, with some in the presence of 10 accredited journalists and a small proportion in open court.
The Lord Chief Justice is expected to give his ruling on the media challenge in January.