It's Friday night in Sheffield and, at the old Robin Hood pub, the conversation is growing lively. "It would be a fantastic experience to see you strip off and see you two play with each other. Then I would join and play with my wife if she lets me," says Simon, a chubby, middle-aged Yorkshireman with a cheeky grin. His wife Toni, who is slim and curly-haired and looks a decade younger than him, gives me a reassuring smile as I nearly drop my notepad on the floor.
"Don't worry love, he's only joking," she says with a laugh as I try to focus on the blank page instead of the various semi-naked people who are casually walking around nearby.
The Robin Hood is no ordinary pub. Once a watering hole for local steelworkers, it went through a radical makeover nearly a decade ago. The dartboards were replaced with large TVs showing hardcore porn, the pool table made way for pole dancing poles, an S&M dungeon was added, and the Robin Hood acquired an alternative identity as "La Chambre", one of Britain's most successful swingers' club.
Soon to celebrate its 10th anniversary, La Chambre is still going strong. Indeed, it now claims more than 40,000 members, ranging in age from 18 to 70. There are, I am told, an estimated one million swingers in the Britain, and the numbers are increasing.
"The swingers scene has changed a lot over the past three years," says 39-year-old Craig Wood, the manager of the club. "The average age has dropped, they all used to be 50 plus, nowadays you get 20-year-olds coming here as well. Sometimes we even have to check their passports."
To be able to join the private members' club you have to fork out between just £10 and £35 in an annual membership fee, and between £5 and £25 on the party nights, depending on if you are a single woman, man or a couple.
Craig, who has been working at the club since it opened, explains: "There are more couples and single guys who want to join than single girls so we subsidise the ladies' fees. It's difficult for a single guy to walk through the door, never mind a single lady. But single ladies can come on the 'couples only night' as well, because couples never complain if a single lady wants to join them for some action whereas they do mind a single bloke butting in."
La Chambre is open from Friday to Monday throughout the year. The "what's on" schedule gives outsiders a good idea of how it works, listing themed nights such as Rocky Horror and St Trinian's alongside sexual preferences nights such as "Transsexual gang bangs" and "Squirters – Cum one cum all, you can do it. A wet time will be had by all." Sundays is the "chill out" day where people come for a takeaway and a "play".
The club was established by Craig's parents-in-law, Barry and Marie Calvert who have been happily married for more than 30 years. Swingers since the early 1980s, Barry and Marie felt that there was a gap in the swingers market and set up La Chambre to cater for those who were fed up with the notorious "key parties" and dodgy sex clubs that catered for the more sexually liberated at the time.
The club itself has six main "play areas". The ground floor consists of a large bar and dance area with pole dancing and porn to get customers in the mood. Also on the ground floor is the "Roman bath" complete with a pool and sauna. The cellar has been converted to an S&M dungeon complete with stocks, whips, dentist chairs and "grope boxes". The first floor has four rooms; "Karma Sutra", "The Boudoir", "Manhattan Skyline", and the "Nights of Arabia" room. Each room is equipped with plastic coated beds and bins for used tissues and condoms. Customers who don't wish to take part but want to watch others have sex can do so through the big windows in each room.
There are also a number of private rooms where consenting couples can have sex and be watched by others. "One of the best moves we ever made was to install these private rooms which also have holes in them for your eyes, your cock and hands. That way couples can just use the bits they want," says Craig as he gives the evening's newcomers the grand tour of the club.
Saturdays are reserved for couples only and single girls whereas Fridays are open to all singles and couples. As Craig takes the newbies around the club the more seasoned swingers lounge around in the hallways wearing nothing but towels. In the corridors leading into the 'play rooms' the newcomers are saluted by erect penises poking through the many glory holes, hoping to receive some TLC.
The atmosphere in the club is relaxed but with an undercurrent of excitement and sexual tension. As the newcomers strengthen their nerves with beverages in the bar, regulars Toni and Simon are just about to get ready to mingle. "We have been coming here for four years and we love it," says Toni, a 40-year-old medical receptionist from South Yorkshire. "It was really my friend's fault that we came here in the first place," adds her husband Simon, 50. "We were at a black-tie do together and he started telling us about this club. We talked about it for a couple hours and he ended up coming back to ours for a threesome."
As with most couples who attend swingers' clubs, Toni and Simon are adamant that their swinging activities don't constitute cheating. "Here we have sex and a play but that's it. I'll make love to Toni when we're at home and I won't do that with anyone else," says Simon.
"To be able to swing you should have a very strong relationship. We trust each other 150 per cent and we always make sure that we set boundaries for what we can and cannot do and stick to them no matter what," adds Toni. "We enjoy seeing each other have sex with others. It gives me a kick seeing Simon with other women, probably because it is taboo. But we don't ever get jealous, sometimes we both go 'you never do that to me at home', so if anything our own sex life has improved by coming here and picking up tips," she says.
The couple have two grown-up daughters who know about their parents slightly unusual carnal activities. "One of our daughters came with us last weekend because she wanted to know what it was like. She thought it was going to be seedy but when she got here she realised it was just filled with normal people. She went around on her own and did some glass collecting, because she felt safe and comfortable to do so," says Simon who often helps Craig to show new couples around the club.
Perhaps the most surprising thing about La Chambre is how very normal it feels; people chat about football transfers and the credit crunch as much, if not more than, they talk about sex. It is only after you leave the club you realise that you have just witnessed something unusual.
"Swingers exist in every part of society, there is no specific type that comes here," says Craig. "We get every type of person walking in through these doors; young and old, fat and skinny, black and white, rich and poor. Your mother or your aunt or your boss could turn up – it has happened many a times before," he says, laughing, and goes on to describe how many old teachers and work colleagues his staff have encountered in the club. "But as far as I'm concerned whatever happens in La Chambre stays in La Chambre; those are the rules," he adds.
Although the bulk of La Chambre's clientele are couples who come together, there is also a high number of people who come alone. Tony, a 47-year-old married sales manager, has been coming to the club for four years on his own. "I have been married for 28 years and I hope to be married to my wife for another 28 years. I love her to bits. She was my first serious girlfriend, and in the beginning we were both as bad as each other and then kids came along."
"Sexually we are chalk and cheese; she is happy to get it on at home once a week whereas I would like to get it on three times a week every week," he says.
Tony is certain that his marriage is happier and more stable as a result of him attending the club. He hasn't told his wife about visiting the club but he is pretty sure she knows about it: "We haven't openly discussed it, but she opens mail for me from here," he says.
"Basically I'm not looking to fall in love with anybody else or for anybody else to fall in love with me. One thing that this place can give you if you can get your head around it is pure recreational sex. You can come in, have a good time and then go home. It starts and stops here, and this is more honest than me having an affair."
That total honesty is the key to a happy relationship is something of a consensus among swingers. Craig the manager, who has seen more successful and unsuccessful swinger relationships than most, says: "Swingers don't think they're cheating on each other because they have gained permission."
"Couples come here and, in each other's company, sleep with several different partners. They're doing it together so there's no deceit and they've given their consent. If one of them would do anything with someone else behind their partner's back they would be heartbroken. It's not about jealously; it's about the lying and the unfaithfulness. That is cheating."
For a swinging relationship to be successful both parties need to be happy with the boundaries they set. There is no point trying to repair an already unhappy relationship by stripping off and jumping into bed with strangers.
Ashley Lister, author of Swingers: True Confessions From Today's Swinging Scene and Swingers: Female Confidential has been researching the British swinging scene since he found out that a few friends of his were active swingers. "The best thing about swinging is that people are able to have so much fun in an open and honest atmosphere with each other," he writes. "When swinging works for a couple it seems to work very well for them and they are able to transcend honesty. They have gone beyond jealousy.
"But it's worth remembering that swinging works for some people and not for others. The negative side of swinging is that when it doesn't work it is like watching a car crash."
Craig, who is a swinger himself, agrees: "We always say, if you swing you have to have a strong marriage or relationship. Don't come in here to repair your marriage because it won't work. Every single week I get people crying on my shoulder. But that's not to do with the swinging scene; it's to do with problems in their marriage."
"But generally swinging brings people together. It's a very social event and it can make relationships stronger. A swinger's life can be a fantastic one filled with honesty as well as great sex."