Angelina Jolie is “is a jealous, cunning liar” who cheated on Brad Pitt and slept with her mother's boyfriend, according to a US tabloid which claims to have the inside scoop on two proposed tell-all books.

As Entertainmentwise previously reported, Hollywood's 'golden' couple are preparing to do legal battle with former bodyguard Mickey Brett to prevent him from divulging intimate details that they would rather be kept private.

Now controversial British biographer Andrew Morten – whose unauthorised Tom Cruise biog reportedly attracted legal threats – has confirmed he is working on expose of his own.

Amongst the dirty laundry ready to get to a public airing is the time that Angelina slept with her late mother Marcheline Bertrand's man, it's claimed.

“Marcheline and her guy had a huge fight, and Angie saw her chance to seduce him,” an insider tells Star magazine.

“Angie cried and begged March to forgive her. Of course, March did.”

Another explosive revelation is said to involve Angelina's "hush-hush liaison with one of the biggest names in rock," during her relationship with Brad.

“Mickey the bodyguard knew all about this relationship,” says an insider. “And the details are pretty hot!”

Angelina & Brad in pictures