The pair had a FOUR NIGHT hotel lock-in

Danny Dyer, by his own admission, has been ‘tempted by forbidden fruit’ in the past, confessing to cheating on his partner of 20 years Joanne Mas on more than one occasion. But last week it was claimed he had a six-week affair with Girls Aloud singer Sarah Harding in 2012 as they shot scenes for their movie Run For Your Wife.

In the film, ironically, Danny plays a taxi driver juggling two wives, portrayed by Sarah and Denise Van Outen. During this time, sources say Sarah had no idea Danny and Joanne were still together.

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‘For a while, Sarah and Danny were head over heels,’ an insider explains. ‘They had a wild relationship. He fell in total lust with her.’

The relationship is thought to have played out in a Holiday Inn near the set, where Sarah and Danny spent six weeks together while filming.

There was even a point when Sarah and Danny were forced to spend four days in a row together in the hotel. Actress

Kellie Shirley, 35, who was also in the movie, said at the time: ‘It was when the riots were going on in London, so we all got stuck in the Holiday Inn for four nights on shutdown.’

The source says Sarah believed Danny was single and living with his dad in London’s Canning Town, adding: ‘Sarah thought she and Danny were a perfect fit. They both really enjoyed a good time and she loved being with him.’

Danny Dyer and wife Jo in 2006

An on-set eyewitness at the time claimed the two of them were openly flirtatious. ‘We spotted Sarah’s hand on Danny’s leg, then her lips on his neck, they then went to the toilets together,’ alleged the source.

But Now understands the affair came crashing down when Sarah learned the truth about Danny’s long-term relationship with Jo. Despite this, in 2015 she commented: ‘Hope ur good babes x,’ on a photo Danny posted to his Twitter feed of his son Arty.

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Previously discussing his cheating on Jo, Danny admitted: ‘I’ve done so many things I’ve regretted. I’ve royally f****d up with my missus. I got caught doing some things I shouldn’t have. I hate myself for what I did and being tempted by forbidden fruit.’

He added: ‘I have birds throwing themselves at me every f***ing day I leave the house – of course I do. I like the power of it.’

As Now went to press, neither Danny, 39, nor Sarah, 35, had commented on the story but insiders claimed his marriage to 39-year-old Jo – who proposed in 2015 before they tied the knot a year later – is struggling as a result.

‘It looks like the marriage is under pressure once again,’ a source claims. ‘Joanne’s forgiven a lot of what Danny’s done over the years, but it can’t go on forever.’