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CLICK HERE to email the KSL Investigative TeamDebbie Dujanovic Reporting

"Everyone has shared their partners with everyone else in the room."

"You're in happy valley and you think nothing like that could happen."

An Eyewitness News Investigation takes us inside a delicate subject few people like to talk about -- infidelity, couples cheating, in secret, in the open, and joining a movement that appears to be gaining momentum.

We heard persistent rumors that spouse-swapping and adultery is commonplace in certain suburban neighborhoods. We discovered those rumors were based on at least some truth. People told us they were being recruited -- marriage counselors say they are seeing more if it.

There aren't statistics or easy answers, but it's clear the effects can be devastating.

Love, commitment, holy matrimony. In Utah, where marriage vows and family values run deep.

Woman: "They said it was more exciting when their spouse was involved."

This story will open eyes to something many would like to keep secret.

"It was taboo within their religious background."

"I thought, this can't be happening here. This is Utah."

Sometimes it's kept very quiet, among neighbors and friends. Other times, it's out in the open. Studies show infidelity is to blame for more than half of divorces in Utah. What we found surprised even experts.

We knocked on doors, attended a party. We heard stories by phone, by email, but nothing could match what we heard in a pocket of Draper.

"Something was wrong with every other neighbor in that neighborhood."

Her husband's indiscretions shattered their marriage.

"Intensely, intensely painful. It's the hardest thing I've ever been through in my life."

The divorce final, he remarried one of their neighbors within a week. It seems adultery ran rampant. Up the block it was consensual with other married neighbors cheating together.

People told us they moved to get away from it and stayed inside to avoid it. Across town one woman told us she just wanted to run from it:

"Everyone in the room had shared their partners with everyone else in the room. These people had been married five, 10, 20 years."

She and her husband were invited to a barbeque with couples from Draper, Provo, Sandy and Salt Lake. A doctor made a move.

"He's hitting on me, like he's single, and his wife's sitting right there. I think, there's another motive to this party and it's not just to hang out and meet new people."

They got out of there.

While there's no data, experts say it's proof of a trend.

Vicky Burgess/Ph.D. Clinical Psychologist: "I think, because sexual relations and sex itself is more open, I think we're seeing more of it."

We found there are several parties where couples can meet.

Randy Chatelain, Ph.D./ Marriage and Family Therapist: "I believe this kind of behavior is going to catch up with a couple, because where does it stop? What more do you have to involve to create the high?"

Hundreds of couples pack a popular Sandy nightclub.

"A lot of people nowadays have fantasies and they want to fulfill them with their significant other. This is the best way to do that."

This man, who asked not to be identified, built a business, helping couples meet at parties. His website suggests spouses can be in love and still enjoy sex with others.

"They figure, 'I would much rather do it with the person I love than have them do it behind my back.'"

From the looks of it, he's pretty successful. He has 4,000 members living in Utah. How fast is it growing? Four years ago there were 150 members.

How common is it? Posing as a married woman, we signed up on a website aimed at so-called "swingers." In six days, 70 married men, most from Utah, ask to start a fling.

CLICK HERE to email the KSL Investigative Team