It’s a moonless night in November. A woman is walking down a London street. Out of the shadows step two men in balaclavas. The men grab the woman. She struggles, but they bind and gag her and bundle her into the back of a blacked-out people carrier. “Everything’s going to be fine,” they whisper in her ear. Five minutes later, her boyfriend receives a text message. “Follow these instructions if you want her back,” it says. Over the following three hours, the boyfriend unravels a series of riddles. Finally, he finds her. She is waiting for him — naked on a bed in a room at a luxury hotel.

This isn’t a scene from a Jackie Collins novel. It’s the real-life enactment of dark and twisted sexual desire, a present from a man to his girlfriend. She knew something would happen, she just didn’t know what or when. The combination of surprise, fear and delayed gratification was enough to ensure that, that night, the couple — one a property developer, the other a media darling — enjoyed the best sex they had ever had.

Concierge services — companies dedicated to answering the every whim of the rich and busy — are everywhere these days. But the company that laid on the kidnapping scenario, French Letter Days, is the first that — officially, at least — is willing to go all the way into the bedroom and beyond. It is the brainchild of Emma Sayle, a former PR girl who fell into the adult-entertainment industry through event-planning. Sayle is one of the names involved with Fever, Cake and Killing Kittens — urbane adult-themed events (okay, orgies) that have all found themselves in the spotlight over the past few of years. Like them, French Letter Days grew out of simple customer demand. “There weren’t any companies out there that would organise clients’ romantic and sex lives,” she says. “And the average person wouldn’t have a clue where to begin if they wanted to make their sexual fantasy a reality.”

If it sounds shady, it isn’t. The operation is 100% above board. “Each experience is tailored to the client’s requirements,” says Sayle. “We send out a questionnaire asking about their sexual thoughts and desires, personal tastes and, most importantly, boundaries. Then it’s just a question of organising the logistics. And just because we’re dealing with sex doesn’t mean we shouldn’t do things in a business-like manner. We all sign a confidentiality agreement, which makes people more comfortable. Once they’ve realised we’re discreet, they relax.”

And what do you know? French Letter Days has been doing a steady trade for the past five months, with, by all accounts, a long line of happy customers trailing behind it. Sue, a fortysomething doctor, had always been a bit of a romantic. Her husband enlisted Sayle and her crew to plan a surprise dinner in a woodland glade, with violin accompaniment and five-star service. “We’d been having a difficult year,” says Sue, fresh from the experience. “We hadn’t been spending enough time together, and we’d got to the stage where we’d forgotten why we fancied each other. The fact that he went to so much trouble to surprise me, to make sure they got it right, reminded us both that we still wanted each other emotionally and physically. It brought the memories back and created a new one. We bonded again, and our sex life blossomed.”

For Elizabeth and Tom, advertising execs in their late twenties, it wasn’t boredom that inspired them to call Sayle, it was the desire to take their sex life to another level. Cue a porn film, starring Elizabeth and Tom, shot at a country house outside London. “We indulged our role-play fantasies: I was the insatiable lady of the manor and he was the gardener who had to do my sexual bidding,” says Elizabeth. “Doing that at home would have seemed silly. This was a total suspension of reality. We forgot our everyday lives and became real porn stars for the afternoon.”

The services don’t come cheap. The least expensive adventure costs about £500, and one client spent £20,000 on a single fantasy. “We’re aiming at wealthier, upmarket clients who are serious about what they want,” says Sayle. “The money goes on the details, everything from your favourite food to exactly the bondage gear you want.”

The fact that Brits are willing to cough up such huge sums of money to spice up their sex lives represents a quantum shift in our attitudes to sex. Ten years ago, sex was at the bottom of the heap, the cheapest form of entertainment available; now, £199 vibrators from Myla, £2,750 “sex chairs” from Coco de Mer and the booming trade in erotic art — 20in x 24in prints by the Japanese erotic photographer Nobuyoshi Araki are selling for £3,500 — are proof that this has changed. These days, we’re not just willing to talk about it and do it, we’re also willing to pay through the nose for it. “People realise that sex is an important part of a relationship,” says Sayle. “They’re willing to spend time and money to make it extremely enjoyable.”

It’s sex as a superior leisure activity. Dangerous, erotic, illicit, but, most of all, fun. “We had one gentleman, a 32-year-old corporate lawyer, who wanted to spend time in a Roman baths with a transvestite dressed as Mickey Mouse, being waited on by he/shes dressed as nymphs,” says Sayle. You really couldn’t make it up.

French Letter Days: 020 7828 4395, www.frenchletterdays.co.uk

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