They decided to try a swingers club. "It was Eric's idea, but I was on board," Janet says. She and Eric hammered out ground rules: no kissing other people, no doing anything without checking with the other person first, and always staying together. "To us, sex is a physical act, but kissing is an intimate act," Eric explains. "That's why it's always off the table." In other words: Pretty Woman rules? "Exactly," says Janet. They finally picked a club over an hour away. The experience was exhilarating, but not their scene. Things didn't get started until after midnight—tough for a couple that goes to bed well before Letterman —and they were freaked out by the atmosphere: One room was filled with people in bondage gear.

After a few failed nights at sex clubs, Janet and Eric were relieved to find Club Relate, a private swingers group owned by a husband-and-wife team, Tom and Lynda Gayle. According to Eric and Janet, the Club Relate crowd is older (members are typically in their 40s or 50s) and, perhaps consequentially, more approachable. "Everyone is so nice, and so respectful," says Eric. "They ask before they do anything with someone else's partner." Lynda keeps a box of latex gloves around, at Janet's request (she doesn't like the idea of germy hands on her), and there are bottles of water and bowls of condoms laid out. Best of all, things get going at 7:30 p.m., and most parties are in hotel rooms instead of nightclubs lit by disco balls.

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Tonight, Lynda is hosting a sex party in a hotel suite. Eric and Janet are eager to go; it's been over a month since their last event, and they're ready to push the envelope even more. They get giddy remembering their first time, when they had sex while strangers watched. "We were up all night afterward," says Eric. "We felt high from the experience." Neither Janet nor Eric say they're addicted to swinging, but it does sound a bit like a drug: "You start to crave it," Eric says. "This summer, I noticed I was thinking about it at work. That's when I said, 'Okay, time to take a break.'"

I ask Janet if she's really never gotten jealous seeing Eric touch another woman. She swears up and down that it doesn't bother her when he does, or when another woman massages him ( massage is pretty much code for any type of touching in the swingers circle). "It's just sex," she says. "Not love. Not intimacy. Sex ."

So where does the couple draw the line? Janet has received oral sex from someone else, but Eric hasn't, nor has he performed it. Janet explains that this is because she's terrified of him getting a sexually transmitted disease. (It's an interesting double standard; Janet didn't use protection the last time she received oral sex from a stranger.) As for emotional boundaries, "I'd be jealous if he were to do something without me there," she says. Eric is quick to reassure her: "That would never happen." Their attitude toward swinging is that they both play or they don't play—end of story. "It's all centered around what makes us happy as a couple," Janet says. "It's always been about us , for us . That's why I think it's helped our marriage."

The action doesn't start for another few hours, so I accept Lynda's invitation to attend the orientation for Club Relate newbies. When I enter the suite—the same one that will be used for the party later on—I see four others already seated, looking nervous. There are two single men, both older, short, and bald. There's also a somewhat mismatched married couple: She's young and beautifully exotic; he's an ersatz Paul McCartney and has a good 15 years on her. She nuzzles him sweetly.

Thirty-nine people have RSVP'd for tonight's party. It sounds like a lot, and I envision a sort of Hieronymus Bosch painting—this beige hotel suite writhing with bodies. But Lynda explains that it won't feel overcrowded, because "lots of people will just be watching." (True, people take up less space when vertical.) Then she outlines the rules: no alcohol, no drugs, and if someone propositions you and you're not into it, just say, "No, thank you, but thanks for asking." This particular flavor of swinging is all about manners. Most clubs have the no-thank-you rule, but Lynda has added the cordial nicety of the second part. It makes sense. Rejection is one thing, but rejection in front of a group of people while naked? Ouch .

As we file out of orientation, the suite's ambience is quickly transforming from convention-center bland to bow-chicka-bow-wow thanks to shades thrown over the lamps and twinkling tea lights surrounding the Jacuzzi tub. I walk to my car, and out of the corner of my eye, I see Eric and Janet heading in to the hotel. We wave to each other as they go to join the rest of the group.

The next day, I meet the couple at a Mexican restaurant. Janet wears heels, a sundress, and a big grin. They're both in a contagiously good mood. After ordering breakfast, they start to whisper some of the details from last night: Once the party began, they made a beeline for a massage table. Another man joined them, and he and Eric gave Janet an erotic massage. Afterward, Janet urged Eric to touch the beautiful woman I'd met in orientation while she watched; Eric admits he was intimidated because the woman was so pretty. "It's like an eighth-grade dance," Janet says. "I had to physically push him to go up to her."

They get sidetracked trying to recall all the places in the suite where they had sex, and the conversation devolves into laughter. "It's sensory overload," explains Eric. They have a sort of blissed-out afterglow usually reserved for honeymooners. "She's been really lovey today," he continues. "She keeps saying, 'I love you so much, you're my best friend.' It's nice to hear." Despite the fatigue, they woke up this morning and had sex first thing.

When I ask them what's next, Janet jumps in. She says they've hung out twice now with a couple they met online, and they're hoping a swap—including intercourse—will happen soon. "I'll feel safer with one married couple than the group setting," says Janet. Her rationale: There will be less risk of STDs, because everyone's married, even though it's obvious there's not a lot of monogamy going on. The emotional risk of swinging with one couple doesn't faze them. Janet and Eric insist that if either of them started to feel any sort of emotional attachment to their new friends, the arrangement would end.

Meanwhile, Eric relishes their swinger status—even if nobody knows about it but them. He starts talking about the guys at work, how they go nuts when a hot girl walks by. "They're sex-starved," he says, shaking his head. He looks warmly at Janet. "I don't act like them, because I have enough. I have more than enough." And yet, they keep upping the ante, daring themselves to go further and betting their bond won't snap under pressure. "This has made us brutally honest with each other," Janet says. "Exploring has made us happier. It's still just us, together, in my mind."

Reality check from a doctor

Our resident sexual health expert, Hilda Hutcherson, M.D., is pretty open-minded... but this trend has her worried.

"If swinging isn't something a woman really wants to do, then she shouldn't," Hutcherson says. "It can lead to major resentment." Even when both partners are genuinely curious, it's crucial to set ground rules and protect each other against sexually transmitted diseases. "Just because someone is married doesn't mean they're safe. Even with condoms, you can be exposed to viruses like HPV and herpes," she says. HPV (human papillomavirus) can lead to cervical cancer, of course, but it's also linked to throat cancers—making oral sex riskier than most people think. There are emotional risks too: "One of my patients got divorced after she saw her husband with someone else at a swingers party. She thought she could handle it, but she realized too late that she couldn't," Hutcherson says.

Couples therapist Mira Kirshenbaum, author of the upcoming book I Love You but I Don't Trust You , agrees: "Before a couple does anything like this, they should talk to each other about what their needs are and brainstorm ways to meet those needs that don't involve swinging." She also underlines the importance of establishing rules, and stresses that couples should have an exit clause. "It's essential," she says. "If swinging isn't working for one person, it needs to stop, no questions asked."

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