It’s the biggest showbiz whodunnit since the nation had to guess who shot EastEnders character Phil Mitchell back in 2001.
After Myleene Klass revealed in lurid detail last month how she caught her ex-husband Graham Quinn cheating on her with another celebrity, everyone has been busy trying to guess who the famous woman could be.
Speaking on a podcast, the Loose Women presenter described how she’d walked in on Quinn and the unknown female ‘unzipping each other’ on a balcony at their home during her birthday party, not long before their 2011 wedding.
She claimed Quinn, a former bodyguard who worked for bands such as JLS and The Saturdays as well as Hear’Say – the group that catapulted Myleene to stardom – later blamed the incident on alcohol and apologised.
Publicly, Myleene has yet to reveal the identity of the star – whom she claimed had built a career on a ‘family brand’ – but her revelation sparked an online Agatha Christie-style hunt to establish the identity of the mystery woman.
And I can now reveal that Myleene is willingly sharing the name of the star with people who ask her about the episode. While I can’t divulge her identity for legal reasons, I can confirm that the woman is not, as has been widely rumoured, a singer.
‘I saw Myleene recently at a do and she told me who it was,’ says my informant. ‘It was jaw-dropping, you would never, ever think it [was the person she named] but, suffice to say, all of the names out there are wrong, the rumours are wrong.
‘Myleene was most certainly right when she said that the woman has built a career on family values. While Myleene has decided not to come out and tell the world, she was certainly not keeping her mouth shut when it came to one-on-one conversations.’

Myleene Klass and her ex, Graham Quinn, in 2005

Myleene last month revealed that Quinn cheated on her with another celebrity just six months before their wedding
Which may be unwise. For I can also reveal that Myleene and the other woman have both got lawyers involved. One source says: ‘It is no longer something flippant, it is all being treated extremely seriously now. The mystery woman definitely does not want her name out there. It feels rather brutal.’
So how did it come to this? To recap, Myleene stumbled upon her husband and the woman mid-clinch 14 years ago. Myleene told the relationship expert Paul C Brunson on his We Need To Talk podcast: ‘It was my party. They weren’t having sex, but they were unzipping each other. [They said] “It’s not what you think,” but it is what I think. It’s the first thing they both said.
‘I kicked everybody out of the party, including his mum and dad. They went back to Ireland. And his dad said, “he doesn’t get it from me.” I was like, “OK.” I just remember that being quite a weird thing to say.’
Myleene admitted she struggled to come to terms with the way the woman involved continued with her own family life as normal after the run-in.
‘I’ve made peace with that situation now,’ she said. ‘But, for a long time, it was very difficult to see their life… Not that I would wish that on a family. I don’t know, I feel conflicted.
‘But my life literally just broke apart very, very publicly. And their life, they’ve managed to continue building a family brand on it and it felt so difficult for a long time. This is the person I caught him with.’
After her revelations, Myleene took to Instagram to say she was happy her account of the incident ‘went viral’ because it ‘reached the people who needed to hear it’.
She added: ‘I have quite literally tens of thousands of messages of love and support for me and my family. I took a long time to learn there’s strength in vulnerability.
‘All this to say, at 47, I’ve finally found my voice and it’s clear, unapologetic and brutally honest. To those that fear its truth, you probably have reason to.’
Myleene ended her post with the Biblical quote: ‘“And the truth will set you free,” John 8:32,’ before adding her own words: ‘And then some.’
Since the story broke, showbusiness fans have tried to identify the woman at the centre of it by poring over paparazzi photographs of famous names arriving at Myleene’s birthday parties and checking to see if she’s stopped following anyone on Instagram.
Quinn, who now lives in Ibiza, has yet to speak out on his former wife’s allegation. He was, however, seen holidaying with Marvin and Rochelle Humes on the Spanish island earlier this month.
They hired a private boat to take them to the neighbouring island of Formentera, where they visited the Beso Beach bar and raised a glass to Quinn, who had recently celebrated his birthday.

Myleene with her two teenage daughters, Hero (left) and Ava (right)

Singer Rochelle Humes posted photos of her and her husband’s, Marvin Humes (left), trip to Ibiza, where they saw Quinn (second from left)
Their meeting, which was shared on Instagram by the Humeses, ensured that Rochelle, a singer in The Saturdays, joined the list of ‘balcony clinch’ suspects. Her former bandmate Frankie Bridge is another.
While Myleene is understood to not exactly be keen on either of the stars because they were ‘extremely loyal’ to Quinn, I can confirm that neither is the woman in question.
My source says: ‘Rochelle absolutely loves Graham, they are really close friends. In fact Marvin is one of his best mates. They were a huge support to Graham when he and Myleene split up, as was Frankie. But that’s it, there is nothing more to it than that.’
Rochelle and Frankie, who is married to former England footballer Wayne Bridge, previously enjoyed a close friendship with Classic FM host Myleene.
In fact, back in 2012, Myleene and Frankie, both hosts on Loose Women, attended Rochelle’s hen do. However, they have not appeared together on the ITV show since an awkward episode last year. Neither Rochelle nor Frankie has commented on the matter.
But now my snitch has a warning for the woman who did have a liaison with Quinn: ‘Watch out, it’s not [going to be] long until your name comes out.’
They say: ‘If Myleene told me, then she is most definitely sharing the name with other people too. If I was this woman I would watch out!’
Despite the cheating allegation on the balcony, Myleene married Quinn after they had spent more than a decade together, in an idyllic ceremony in October 2011, with just 16 guests in attendance.
However, their romance came to a dramatic end six months after the wedding, with Myleene claiming he walked out on her and their two daughters, Ava, now 18, and Hero, 14, something he has always denied.
The star spoke earlier this month about her ‘miserable’ wedding day, saying: ‘I literally cried the entire reception.’
Myleene also revealed fresh details about the split, which came after she flew out unannounced to the place where her husband was working because she suspected he was being unfaithful to her. After confronting him at his hotel, she told Brunson: ‘I knew there had been someone in that room.’
Myleene also said the financial aspects of the divorce had taken a heavy toll on her mental health: ‘I couldn’t breathe. Finances were spiralling. I thought, “I’m going to lose everything.”’
But she has since found another partner, PR guru Simon Motson, 49, with whom she has a son named Apollo. They met on a blind date in 2015 and have now been engaged for more than five years.
Those who know Myleene wonder what Motson makes of her former relationship being discussed across the nation, though they concede that she very much ‘does what she wants’.
‘Myleene is a strong woman who takes no prisoners,’ says a friend. ‘She is determined and she rarely lets anything go.’
In what amounts to a warning to the mystery woman, the pal adds: ‘Woe betide anyone who crosses her!’