A new biography on Hollywood legend, Jack Nicholson, reveals that he had a sexual relationship with Meryl Streep while the actors starred in the 1987 film, Ironweed.

The book reveals that Nicholson was juggling relationships with Anjelica Huston, Veronica Cartwright, the occasional Lakers cheerleader, and possibly Streep.

The actors were rumoured to have grown unusually close during filming, and an unnamed source told the Los Angeles Herald Examiner that “whatever is going on inside that Winnebago it’s starting to get out of hand, to the point where it’s embarrassing a lot of people on the set.” However, Nicholson had a reputation for being a womaniser and had been referred to by friends as a “better swordsman” than Warren Beatty.

The book, entitled Nicholson, also explores the star’s struggles with drugs and his weight.

It reveals that Nicholson was a “chronic drug user in the early years of his career,” experimenting with LSD in the early 1960s and taking cocaine and marijuana.

The book claims that Nicholson wrote the screenplay for the 1967 film The Trip while “on acid” and “regularly got stoned and dropped acid” while writing The Monkees psychedelic adventure comedy film Head.

The book alleges that he met potential investors for the cult Peter Fonda and Dennis Hopper film, Easy Rider, “with a joint”.

Nicholson’s drug experiences, according to the book, were life-changing.

He believed after taking LSD the first time that he had seen the face of God, and he also had castration fantasies, homoerotic fear fantasies, and revelations about not being wanted as an infant.

He could confront the persistent problem of premature ejaculation that had plagued him ever since he had begun sleeping with Georgianna Carter while tripping, and all of these visions and revelations were connected.

Despite being able to woo some of the world’s most beautiful women, Jack Nicholson struggled with his weight at the height of his fame.

After hiring ‘dietrix to the stars’ Judy Mazel, he soon piled on the pounds after filming Postman.

The new book also details the question of Jack’s paternity after he spent the first 37 years of his life believing his parents were John and Ethel May Nicholson.

Instead, he was told in late 1974, his mother was actually his older sister June, and his father was Don Furcillo-Rose, a sometime musician.

Nicholson was devastated by the news, and despite doing his best to curtail the publication of the story, in 1977, the tale behind Jack’s alleged birthright was published in Sunday morning supplement Parade, in a piece by columnist Walter Scott, who said that his source was Furcillo-Rose.

Jack tracked down his phone number and called him to ask if he was his real father.

Furcillo-Rose replied yes, adding he was also part of a love triangle between June and Ethel May, which is why she occasionally let him stay at the house.

Stunned, Jack would not accept the news and released a statement calling the claims “false and defamatory”.

Furcillo-Rose refused to take a blood test when contacted by Jack’s legal team, and the star never talked to him again.

Jack Nicholson is best known for his roles in classic movies, such as One Flew Over the Cuckoo’s Nest, The Shining, and Batman.

He has won three Academy Awards and has been nominated for a further nine.

Despite his success, the book reveals that he had a tough upbringing and was often in trouble as a teenager.

He was “arrested several times for fighting, and once for breaking into a grocery store.”

However, he found his true calling in acting and moved to Hollywood in the 1950s.

Nicholson has only been married once, to Sandra Knight, with whom he has a daughter, Jennifer, 50.

He has two children with former girlfriend Rebecca Broussard, a daughter from his relationship with Danish actress Winnie Hollman, and a son from a romance with actress Susan Anspach.

Despite his reputation for being a womaniser, Nicholson remains charming and is still friends with Meryl Streep.

Last year, Meryl picked Jack to “shag” while appearing on Andy Cohen’s Bravo show, Watch What Happens Live.

Nicholson has also had a successful career as a writer and director.

In addition to writing the screenplay for The Trip, he directed two movies, Goin’ South and The Two Jakes.

Despite his success, the book claims that Nicholson’s drug use nearly ended his career.

However, he has managed to overcome his demons and remains an icon in Hollywood.