Unbroken star Jack O'connell has emerged as a frontrunner to portray John Lennon opposite Nicholas Hoult as Brian Epstein in a new biopic about the Beatles manager.

Mandela: Long Walk to Freedom filmmaker Justin Chadwick is in talks to direct A Life In The Day from a script by Tony Gittelson, with the two young actors expressing interest in tackling the key roles, reports Deadline.com.

Epstein famously discovered the Fab Four during an appearance at the Cavern Club in Liverpool, England in 1961 and helped to turn them into superstars before he died from a drug overdose in 1967, aged 32.

His close relationship with Lennon has long been the subject of speculation they were more than just friends. The rumors even inspired the 1991 film The Hours and Times, which explored the rock myth that Epstein, who was gay, once slept with the Imagine singer during a vacation in Spain in 1963.

Lennon's widow Yoko Ono denied the reports this week (begs12Oct15), but claimed her late husband "had a desire" to experiment with his sexuality.

She told TheDailyBeast.com, "I think he had a desire to (have sex with other men), but I think he was too inhibited. No, not inhibited. He said, 'I don't mind if there's an incredibly attractive guy.' It's very difficult: they would have to be not just physically attractive, but mentally very advanced too. And you can't find people like that."

Lennon was shot dead outside the couple's New York City apartment in 1980.