ACTRESS Sadie Frost seductively peeled off her clothes and slowly swung her slender hips before sliding out of her knickers.
Then, starkers, she sat down on rocker Danny Goffey's knee and started kissing and caressing him.
Looking on was frisky Frost's husband, Hollywood superstar Jude Law and Goffey's sexy singer/model girlfriend, Pearl Lowe.
According to a sensational report in British tabloid the News of the World, the four friends had all been boozing heavily one night while on holiday in Greece in 2001. It was then that horny Frost, her inhibitions drowned in wine and champagne, put on a CD and started doing her impromptu striptease.
A friend of the two couples told the News of the World that Frost then shocked the other three by blurting out: "Hey, why don't we swop?'
"When Sadie peeled off her knickers and sat on Danny's knee there was no going back."
According to the source, there was a brief, stunned silence after Frost suggested the couples have sex with each other's partners. "Then the other three looked at each other and just said, 'Yeah, okay, why not?'
"It wasn't an orgy or anything like that, just plain wife-swopping."
Frost, 36, had been flirting with Supergrass drummer Goffey, 30, all night before her striptease.
She and Law, 32, had been married for four years at the time, while Goffey and 34-year-old Lowe had been an item for six years. Sadly, that night of passion turned out to be the beginning of the end for the famous acting couple's marriage.
Initially, Lowe wasn't impressed with the Hollywood hunk. "She told me the sex with Jude was okay but not earth- shattering," the source said. "He had a fairly fit body and was quite muscular as he'd been working out.
"But Jude was just averagely endowed and Pearl said that he certainly wasn't as well endowed as Danny. And the sex was over in 10 minutes - very straight-laced missionary man. It was just fast raw sex, fuelled by lust and booze. Pearl said he wasn't such a good lover as Danny. Apparently that made Danny feel relieved later as he was, unsurprisingly, a little anxious that Jude Law, movie superstar, was having sex with his girlfriend. It must have been on his mind while he was making love to Sadie."
The following day, Lowe got over her disappointment, and Frost was raring for more. So that night they were at it again, going off to separate bedrooms with each other's partners.
The foursome made no secret of their wild sex sessions and flaunted themselves in front of other shocked friends who visited the villa.
"During the remaining part of the holiday, they paired off several more times," said the source. "Pearl said it was like they couldn't get enough of each other."
But Law was becoming obsessed with Lowe. "As the holiday wore on, Jude got more and more blasé about what was going on. He kissed Pearl often - not just when they were in bed together. Sometimes he kissed her passionately right in front of Danny and Sadie. They were being quite open and some of the house guests watched in amazement at what was going on.
"Danny got a bit irritated but Pearl kept reassuring him that Jude wasn't exactly the last of the red-hot lovers!"
After two weeks of non-stop sex by the sea, Lowe and Goffey left. But the four couldn't leave each other alone.
Recalled the source: "Pearl told me Jude couldn't get her of his mind and started phoning her. Then, when he came back to London, he started e-mailing her, telling her how much he really adored her.
"She was really flattered and I suppose was swept away by it all."
The wife-swopping continued in London. "Danny and Pearl arranged for Sadie and Jude to come to their house and after a few drinks they paired off again.
"Pearl said they were in separate bedrooms, never as a foursome, and Sadie and Pearl definitely didn't have anything lesbian going on. They would get really drunk on wine first."
Then the sex games turned to war. One day Frost discovered that Law had sent Lowe passionate e-mails suggesting that they have an affair behind the backs of their partners.
Frost flew into a rage and smashed up the house. "After that, things really changed. Jude cooled a lot towards Pearl and they never made love again," said the source.
Eventually, in 2003, Law and Frost announced that they were splitting up - although they certainly didn't let on anything about the wife-swopping. Goffey and Lowe - who have two children - also went through a bad patch but are still together.
The film stars, though, are now both dating other people, and have joint custody of their children.