Justin Timberlake cheated on Cameron Diaz with a Playboy bunny during the early stages of the celebrity couple’s relationship, according to the model.

Zoe Gregory, who moved into Hugh Hefner’s famous LA mansion in 2001, says she ‘hooked up’ with the Sexy Back singer at the property’s infamous grotto after meeting him at a party.

In an exclusive interview with us the British model, now 49, said Timberlake initially declined her advances by telling her he was dating the Charlie’s Angels star.

But when Gregory teased that his girlfriend was ‘not with you now,’ he agreed to strip down to his shorts and jump into Hugh Hefner’s indoor pool, she claims.

Former Playboy model Zoe Gregory (in blue cap) revealed she ‘hooked up’ and ‘fooled around’ with Justin Timberlake (front right) when he visited the Playboy Mansion while he was dating Cameron Diaz

Timberlake, who was 25 at the time, began dating Cameron Diaz, then 34, in 2003. Gregory claims she hooked up with the singer during the early stages of his relationship with the actress

British-born Gregory moved into Hugh Hefner’s famous LA mansion in 2001 as one of his seven girlfriends

‘He didn’t want to look like a wimp. We both got in the grotto and we both got our kit off – down to his shorts – and we ended up fooling around,’ she told us.

‘I didn’t have sex with him, but we had a fondle and we made out.’

Gregory’s revelations could prove embarrassing for the singer dubbed ‘trouser snake’ by fans.

Timberlake, 43, had been known for his womanizing on the road before he settled down with actress Jessica Biel, 41, in 2012 and had two children.

Last year, the former NSYNC frontman became the subject of explosive allegations when ex Britney Spears wrote in her memoir that he had encouraged her to have an abortion during their ill-fated relationship.

Timberlake’s new album, Everything I Thought It Was, is out next month and his team will be eager to drum up positive publicity ahead of the launch.

But while promoting her new book, From Britain to Bunny – released last month –  Gregory says the pop star could not resist her advances after she spotted him at one of Playboy boss Hefner’s star-studded parties in the early 2000s.

The former Playboy model recalled how Timberlake stripped down to his shorts and jumped in the mansion’s infamous grotto (pictured)

Gregory recalled meeting several celebrities, including wrestler Stone Cold Steve Austin during star-studded parties at the mansion

The former Playboy model was pictured with Donald Trump and sex therapist Dr. Ruth Westheimer at an event

She was one of several bunnies that shared a bed with Hef at the mansion at the time, despite the fact he was already in his 70s and relied on Viagra to perform.

Timberlake would have just started seeing Diaz having reportedly met her at the Kids Choice Awards in 2003.

The actress was 34 at the time, while Timberlake was just 25. They went on to date for four years before announcing their separation in January 2007.

Gregory, meanwhile, split with Hefner in 2004 and admits that she cheated on him more than once during their three-year relationship.

Speaking from her home in Miami, she said: ‘They would rent the back of the mansion out for events about three times a month.

‘It was great because so many superstars attended – Nicolas Cage and Eminem – I met them all.

‘We weren’t allowed to go to these parties, but me and two of the girls would sneak down there once it was past Hef’s bedtime.

‘We would just have to watch out for the security guards on patrol because some of them would let him know.

Zoe was one of a harem of bunnies who lived at the property and shared a bedroom with Hugh

Timberlake would have just started seeing Diaz having reportedly met her at the Kids Choice Awards in 2003. The couple called it quits in 2007

Timberlake, 43, was known for his womanizing on the road before settling down with actress Jessica Biel, 41, in 2012. The couple (pictured in 2022) have two children

‘It would be a telling off if he found out. And if you struck out more than three times he would kick you out of the house, so you had to be careful.

‘I met so many famous people during those nights out. But I only hooked up with a couple and one of them was Justin.

‘He was in the grotto one night and had a big head and said something about Cameron Diaz, because that’s who he was dating at the time.

‘I was like, “Well, she’s not with you now, so what’s up? You’re in the Playboy Mansion so what do you think is going to go down here?”‘

‘He said, ‘Oh Ok!’ He was being cocky because he was drunk.

‘I just wanted to tick him off my list, to be honest. It was literally a five-minute thing and from what I can remember, he was decent.

‘But I was so scared of getting caught that I couldn’t continue for too long. Before it could go any further, we both put our clothes back on and said goodbye.’

Among the stories that Gregory tells in her new book is Hefner’s unique way of remembering the women he had slept with.

Instead of notches on the bedpost, Hef had a huge array of undergarments dating back decades dangling from the bedroom ceiling. Some had been there so long they were covered in cobwebs.

‘I had never seen something like that and I loved it,’ she said.

As Hefner aged his mind deteriorated, Gregory said. ‘The last time I saw him in person was when I went to the mansion for a party. I said hello and he was looking really old and I thought: I don’t want to remember him like this.

Gregory left the Playboy mansion in 2004 when she fell out with his number one girl Holly Madison

‘It was such a centerpiece of his room and I thought, if only walls could talk. I would love to meet the women that threw their thongs up there and hear their stories.

‘The big, gold chandelier  to the right of his bed was covered in thongs from all the girls that had been there over the years. I would say there were a few hundred up there.

‘You could see decades of different styles of panties, going from full-blown knickers to tiny little G-strings. I threw a couple on it before I left, a red one and a tiny little black one.

‘I decided, before I leave this house, I am going to make sure a few of my thongs are up there because it was legendary.

Gregory was one of the Playboy boss’s live-in girlfriends from 2001 but left the Playboy mansion in 2004 when she fell out with his number one girl Holly Madison.

She said she regularly contracted sexually transmitted diseases from Hefner, who died in 2017 aged 91.

But as he aged his sexual appetite dwindled and he liked watching porn more than actually having sex.

‘After he had a few drinks and smoked a bit of weed, you could tell he was in his own bubble. He would lay there and allow everyone to hop on and off him, but he would be most focused on the girls performing and the porn on the TV.’

 But as far as his orgies were concered, Gregory said: ‘I counted 17 girls on the bed one night – that was the most.

‘You couldn’t fit us all on the bed so some of the girls were sitting on the floor waiting for their turn.’

Gregory said she has fond memories of the old man. ‘I wanted to make him happy because he was making my dreams come true.

‘I love that guy, he is my hero, because he set me up for life and he gave me all the opportunities I ever dreamed of. I have not got a bad word to say about that man, it’s all love.

‘I didn’t find him physically attractive. There were certain mannerisms of his I loved because they were so gentlemanly and old fashioned.

‘Men don’t act like that anymore and I loved that, but did I find him physically sexy? No.’

She said she kept in touch with him by phone after she left the mansion but his mind started deteriorating around 2019.

‘The last time I saw him in person was when I went to the mansion for a party. I said hello and he was looking really old and I thought: I don’t want to remember him like this.