When the time comes, dear reader, to hand a super injunction to the cartel that has decided to blackmail you, you’ll need to prepare a few things.

First, a glass-fronted and open plan restaurant on a major high street in London. Next, a couple of plain-clothed police officers to sit in its dining room, a few yards away from your hulking head of security. At the same time, you’ll need to come to a small financial arrangement with the restaurant owner so that the waiters can be replaced with your own people, and so that the back exits can be cleared from clutter and a friendly black cab can idle in the alleyway behind the building.

Meanwhile, you’ll need to position two of your men – tatty and squabbling yet unobtrusive – on the bench outside so that they can profile everyone who’s coming in and out between swigs from fake cans of Amstel (or similar continental lager of your choosing). Finally, you’ll want your adversary to sit down, when he does sit down, in a very low chair with a deep cushion and a high back – tough, you’ll notice, to get out of in a hurry should things turn shooty.

Or, of course, you could just get James Johnstone to do it all for you. Because, when the real power brokers of this world come to the limits of their worldly power, they don’t call for their financial advisors, or turn to their 26-year-old PAs, or dial 999: they ring up the man they call ‘JJ’.

James Johnstone has a voice like the Queen’s equerry and the stature of a fast bowler. He has been a stockbroker, a machine tools salesman, a corporate lawyer, a Storm model, a brewery owner, and, for many years, a barrister. He measures everyone on a scale from good egg to absolute rotter, and can tell both at 40 yards and after six martinis. He can open a safe with a hot potato and a hair dryer (I’ve no idea either), or plan a surprise birthday party for your millionaire uncle in which he’s kidnapped – much to his delight and the horror of his insurers – by ex-Mossad agents.

When I meet him, in his London townhouse, James spools off a stream of household names and bewildering anecdotes, interrupted only by sips from a huge urn of ginger and lemon tea. On the wall of his living room, just above a colourful papier-mâché sculpture made by his son, there’s a framed mid-century Penguin book cover, in tattered orange and black, from the novel 

“It’s from my sister,” James says. “A joke for people who know.” And the list of people who know – 

 know – is long and explosive. Politicians, bankers, movie stars, sovereign wealth billionaires, the wayward sons of industrialist fortunes – the eggs, butter and flour, in other words, of the uppermost crust of a very juicy pie. For them, James is not simply their man in Havana, but their man in London, in Caracas, in New York, in Doha; in crisis, in celebration, in confidence and in cahoots. Anyone these days might have a concierge – but only the most truly interesting people have a

The reasons number into the thousands and span from the life-endangering to the really quite lovely. “My only rule is that I don’t do anything illegal, unethical, immoral, stupid, or boring,” James says. That rule leaves a lot of room to play with. You may need, for example, to rescue a wayward son from the low countries, or track down a priceless diamond tiara at 2am, or purchase a school in England so that you can switch around its term times to fit your holiday schedule, or plan a 25th wedding anniversary for your darling wife. Matters of the heart strings or of the purse strings, then – or, quite often, a tangling of the two.

"James Johnstone measures everyone on a scale from good egg to absolute rotter, and can tell both at 40 yards and after six martinis..."

“A London banker came to me, a real old boy. His son, the heir to everything, was well known on the London party scene – he was one of those people whose only success in life was making a failure of every single one of their ventures,” James says. “The father was convinced that the son’s very attractive new socialite fiancé – a total eurotrash babe who was always on the circuit, they were photographed everywhere together – was a complete gold-digger, and a fairly serious recreational drug-taker: a real old good time girl.” The son, James explained, had been through one catastrophic divorce already, and the father didn’t want anything of the sort happening again, not least for the sake of his grandchildren.

“We had to have proof positive,” James explains. “We needed eyes on and hard evidence. Fortunately, because the townhouse where the couple lived belonged to the father, he was able to give us permission to go and put stuff in, which we did.” James and his team planted bugs and cameras in the master bedroom and the study, and temporarily swapped out the original maids for his own undercover agents. “All the while, it was absolutely imperative that this rather vulnerable son knew nothing of what was happening or that it had been instigated by his father. Because, of course, the investigation could have been wrong.” It wasn’t – not by a Knightsbridge mile.

The patriarch’s suspicions were confirmed many times over, and in more sordid detail than any father should ever have to hear about his son. “The outcome, ultimately, was that the girl was gone, and I can’t imagine that was happy for anybody. At least he wasn’t fucked over by someone he thought he loved. But I found the whole thing really sad on so many levels.”

Much happier are the times when those suspicions are proved false. “A woman called me up because she’d found my business card in her husband’s blazer pocket. And she says ‘you’re the fixer who’s been working with my husband and I know you’re helping him hide something, the way he’s behaving.’” She was absolutely right. But James wasn’t covering up an affair or a blackmail case. “I was planning a secret 25th wedding anniversary party combined with a 22nd, a 21st and an 18th birthday for their children. When all was revealed, she absolutely loved him for it.”

But party planning, even to that exuberant degree, falls at the more manageable end of the fixer’s spectrum. “Quite often you are asked to do the impossible,” James says. “The client knows they’re asking for something that almost certainly can’t be done, because they’ve gone to Kroll [the most established investigation firm in the world] and they’ve turned it down, and then they’ve come to me.”

One such feat was a request by a European industrialist to investigate the head of a tiny state in the Urals, to see just how interfering they might be in the private mining operations of the area. “What they wanted was a preliminary report on an obscure political leader in an obscure country in an obscure language.” Using an international web of contacts high and low, and a barrister’s addiction to trawling through cubic feet of dense and obfuscating paper work, James performed a forensic level of due diligence on the country’s leader. And he found absolutely nothing. “My filing to the client simply began: ‘The most significant thing about this report is that there’s nothing of significance to report,” James recalls.

He then went on to write that this meant that head of state had succeeded in hiding everything of suspicion, and that he had disguised every asset that he had ever owned, and as such, couldn’t be trusted as far as he could be thrown. The industrialist client pulled out of the business engagement, and, soon enough, the Ural premier was outed as a pie-fingered philanderer of the first water.

This is the hair-trigger, laser-sensor knack of the society fixer – a sensitivity to the details (or lack of them) that you, I, and the lion’s share of the global elite would overlook. “Sometimes you know someone’s a bad egg from the second they walk in,” James says. Take the case of the yacht broker in a room at the Carlton Hotel in Cannes (“It’s always the Carlton, for some reason”) who attempted to fluff the egos of some wealthy Middle Eastern clients by selling a moody yacht scheme and name-dropping an apparently soon-to-be-shuttered Dutch shipyard.

“The way he walked in told me something was off. So I went away and did my research.” Where other people sit on Google for an hour or a day, James tells me, he sifts through the backwaters of the internet for two or three weeks. “I found this one old blog post about how this guy had lost his yachting licence in Florida and was banned from selling yachts in Europe, too. I saved my client several million on that deal. They took me for a nice lunch after that.” Other situations require a bit more preparation.

"James is not simply their man in Havana, but their man in London, in Caracas, in New York, in Doha; in crisis, in celebration, in confidence and in cahoots..."

“There may be a case when someone’s pitched an investment opportunity to the CIO of a client’s family office,” says James. “The CIO and the client don’t want to show they’re interested, but they want to find out if there’s anything interesting there. But, more importantly, they want to find out the measure of the man.” In such situations, James will cook up a fictional back story, complete with business cards and an out-of-the-blue meeting proposal, and fly over to have lunch with the hopeful pitcher.

“You’ve got to set something up – generally a very smart business card you’ve created, on which you use your own first name – makes it much easier, in general. You can just say you’re a ‘family office advisor’, and it’s quite hard for them to find anything out about you.” That way, James can press the flesh and size up the pitch under a cloak of utter discretion, without the proposer ever knowing that the client was involved. “Time, hassle and effort is all saved. And I’ll have faded from the scene before anyone knows what happened.”

Such cases involve intelligence by way of information and espionage. But more often than not, it’s cultural intelligence that is most valuable. At short notice one autumn, James had been asked to take a Saudi Arabian magnate to Gleneagles for a spot of deer stalking. “At the hotel on the night before the excursion, my client had seen me wearing a kilt, and had rather liked how the pipe major was dressed, too.”

The next day, before the client’s very brief and largely theatrical shooting trip (the day before they had fished in rivers that they knew full well had no fish in them, just for the experience), the man said he’d quite like to turn up at the top table at supper that night bedecked in full Highland garb. “So I took all their measurements and went off to a tailor that we’d seen on the way through the town, and had all the kilts delivered to Gleneagles in time for him to dress for dinner.”

“Just before we entered the dining room, I was standing outside with the band major, waiting to go in. And suddenly the piper practically choked on his cigarette and said, in this broad Scottish voice: ‘I think that’s your man.’” The Saudi tycoon and his entourage had decided, when dressing, that they should pull the kilts up over their sizeable bellies. “The kilt had risen up, and out from below hung the exposed crown jewels,” James remembers. “He looked like Obelix, with the kilt waistband trucked under his tits. And he just walked in like that – his sporran resting on his stomach like a little bib, smiling from ear to ear.”

It was only when they reached the top table, accompanied by a bewildered silence and the plaintive piping of the band major, that the Saudi guest realised something might be wrong. “‘Don’t you think it feels a bit funny – your arsehole on the leather seat?”, he said. And I said: ‘I’m sure it would be absolutely fine if you just went and pulled it down to the normal place,’”James remembers. “‘Oh,’ he said. And then a big fat grin spread across his face. They all thought it was hilarious.”

If money can’t buy you cultural nous, then it certainly can’t buy you happiness. James’s spool of capers and high jinks is long and cinematic – of limited edition, first-rate Ferrari Enzos rescued from the Malaysian jungles; of $500 million Ponzi schemers chased across the Gulf; of priceless art collections Shanghaied, single handedly, across Europe; of a Holland Park bugging case solved with UV paint. But through it all a quite mundane truth emerges: that, more than almost anything else, these hyper-wealthy clients are looking for companionship, camaraderie, and the opportunity to be treated utterly normally for once.

“Money makes people around you act differently. It brings with it a whole host of intricate problems that are often nearly impossible to solve through conventional means.” As such, if you ever win the lottery, James advises, you should claim the money (“no point it going back to Camelot”), and then get rid of it all within seven calendar days, without telling a soul. “As long as you were happy and comfortable in the first place, that money will only bring you unhappiness.”

At one point, before supper on the deck of a yacht off the Côte d’Azur, the diamond merchant Laurence Graff – a friend and sometime counsel – turned to James and said: “What do you think is the perfect amount of money to be happy?”. James said he didn’t know. Later, when the Tchenguiz brothers had joined them on the deck, the gathered billionaires battered around figures and stats; compared compound interests and bank statements. Once they had all left, Laurence Graff turned to James and said: “How much money do you have in your bank account?”. James said he had “about £2,383”, at the last time of checking. “Well, based on all the evidence

” Laurence declared, “is the perfect amount of money you need to be happy.” Good to know.

“I have had the wonderful opportunity to live vicariously – to enjoy the amazing privilege of wealth without any of the trappings,” James says. But more pleasant than the odd 80-year-old malt or the intermittent borrowed yacht is the satisfaction of the quieter, smaller moments. “Walid Juffali [the Saudi billionaire businessman] once turned to me and said: ‘You’re the first friend I’ve ever had,’” James remembers. These moments form a retainer of a very different kind.

“You’re not always making people happy. But very often you’re making them less 

In this world, it’s a nice distinction. “As for the rest of the time,” James says, pacing about the living room and adjusting the papier-mâché masterpiece on the shelf, “you’re just trying to make life more interesting.”

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