Unbroken star Jack O’Connell says his breakthrough role hurt as he survived on just 400 calories a day

HUNGRY for success? The star of Angelina Jolie’s epic blockbuster Unbroken Jack O’Connell says he was literally starving.

HUNGRY for success? Unbroken star Jack O’Connell was literally starving.

In the lead-up to filming Angelina Jolie’s inspirational drama about real-life WWII hero Louis Zamperini, the 24-year-old Brit survived on approximately 400 calories a day.

“You can’t act your way through a film like this,’’ says O’Connell, who kicked off an arduous three- month film shoot in Queensland and NSW with a sequence in which his emaciated character is “rescued” by the Japanese navy after spending 47 days at sea in a life raft.

In this image released by Universal Pictures, Finn Witrock, from left, Domhnall Gleeson and Jack O'Connell appear in a scene from "Unbroken." (AP Photo/Universal Pictures)

“It did have to hurt and I was willing to take that on the chin.”

After being plucked from the ocean, barely alive, Zamperini, a former Olympic athlete, spent two years in a series of prisoner of war camps, where a brutal Japanese sergeant (played by Japanese pop star Miyavi) singled him out for punishment.

Since Jolie required her key cast members — including Domhnall Gleeson, as Zamperini’s friend and fellow airman Russell “Phil” Phillips — to be scarily underweight for the ocean and prison camp scenes, she shot that footage first.

“We knew we had a mountain ahead of us so we were just going into it swinging,’’ says O’Connell.

In this image released by Universal Pictures, director Angelina Jolie, left, and Jack O'Connell appear on the set of "Unbroken." (AP Photo/Universal Pictures, David James)

Whenever he felt like throwing in the towel, the actor reminded himself that his own discomfort paled dramatically alongside Zamperini’s real-life experience.

But he still describes the film shoot as the “most difficult adversity I have faced in my life — physically, anyway.

“Thankfully I never reared. But I had to accept that I wasn’t going to enjoy it — even if now it feels worthwhile.”

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Even the audition process was gruelling.

Jolie, who first came across O’Connell in the prison drama Starred Up, in which Australian actor Ben Mendelsohn plays the actor’s Cockney convict dad, was impressed by the young actor’s self-tape.

A Pinewood Studios screen test was organised to persuade the executives at Universal Pictures to take a punt on the relatively unknown performer.

In this image released by Universal Pictures, Jack O'Connell portrays Olympian and war hero Louis "Louie" Zamperini in a scene from "Unbroken." (AP Photo/Universal Pictures, David James)

“They told me this crew member would be portraying a guard and that every now and then he was going to come in and f ... k with me. And I was like: ‘okay, sweet’.

“And then, to be honest, it was getting to the stage where it was hurting me and I was like: I can’t just lie here and take another round of that, so I got up and gave him hell too.

“It probably wasn’t necessary in terms of the character — in terms of the story for Unbroken it would probably have resulted in an execution- but it gave Angelina something to show them in terms of resilience.”

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O’Connell says he’s never adverse to a little physical prompting — if it helps him get to where he needs to go in his performance.

“I might be giving away all my tricks here, but I sometimes I’ll give myself a dead-leg or something like that, just before a scene.

“And bear in mind that I didn’t have a name at this stage — in terms of the Universal realm anyway so I really needed to pull it out of the bag. It was actually helpful to take a few wallops here and there.”

MUST CREDIT: Other (see notes)... MUST CREDIT UNIVERSAL PICTURES Angelina Jolie Academy Award winner Angelina Jolie directs and produces UNBROKEN, the epic drama of the life of Louis Louie Zamperini, adapted from Laura Hillenbrand's enormously popular book. The project has a long history at Universal Pictures, which first acquired the rights to tell Zamperini's life story in 1957, planned as a starring vehicle for Tony Curtis as his follow-up to Spartacus. Jolie and Zamperini, neighbors in the Hollywood Hills, have become close friends over the development of the film, as the filmmaker has listened to the war hero recount the incredible incidents of his life over many months of preparation. Zamperini gave Jolie a golden running shoe pendant, a prize from one of his earliest races, which she will wear every day as she helms the film in Australia over the coming months. Jack O'Connell earned the starring role and will appear as Louis Zamperini. O'Connell recently spent several afternoons meeting with Zamperini at his home to hear the man he'll be portraying recount his incredible tale firsthand. Zamperini retains many keepsakes from his adventures in his home. Seeing Zamperini's World War II bomber jacket, O'Connell asked permission to put it on, which Zamperini gladly gave. The jacket fit O'Connell perfectly and became one of the first moments of him inhabiting the life of this legendary hero. UNBROKEN arrives in Australian theatres January 8, 2015. The film is based on Unbroken: A World War II Story of Survival, Resilience, and Redemption by Laura Hillenbrand, who also wrote Seabiscuit: An American Legend. Universal optioned the rights to the book in December 2010. Since being published in 2010, Unbroken has spent more than 145 weeks on The New York Times best-seller list, 14 of those in the top position, and has sold almost 3.5 million copies worldwide. A young-adult version of the book will be published by Random House this coming spring. Unbroken was named Best Nonfiction Book of the Year by Time magazine and won the Los Angeles Times Book of the Year Award for Nonfiction. QUOTES: ANGELINA JOLIE: It will be hard to make a film worthy of this great man. I am deeply honored to have the chance and will do all I can to bring Louie's inspiring story to life. Everyone involved in the film shares this deep responsibility. Like all readers of Laura's book and all people who love and admire Louie, I am a fan who has learned so much. He has made me a better person. LOUIS ZAMPERINI: Angelina is a human dynamo, and I know she will tell this story in the right way. I've received so many letters and talked to so many people who say that Laura's book has helped them when they were going through hard times. I believe the movie will reach even more people with that message. Picture: Notes) Other (see

Keeping O’Connell focused on the days his stomach was grumbling particularly loudly was the long shadow cast by Zamperini, whom he met prior to filming.

“I was under a lot of pressure,’’ he concedes.

“Meeting him was vital. I needed to connect with him, to see the way his brain ticked at the times when he wasn’t necessarily doing much, to see where his neutral was.

“Even though he was 96, he was so much more quick-witted than me. He was very sharp and lucid. That was a bit intimidating.”

During one visit, O’Connell asked Zamperini if he could try on his WWII bomber jacket. When it fit him perfectly, the actor took it as a good omen.

O’Connell says their final encounter — Zamperini died, on July 2, after seeing a completed version of the film — was more relaxed.

“The third meeting, after the shoot, was kind of celebratory. I felt I had done a good enough job to look him in the eye.”

Unbroken has performed well above expectations in the US, where it opened on Christmas Day, grossing $US87.8 million in less than two weeks.

In this image released by Universal Pictures, Jack O'Connell portrays Olympian and war hero Louis "Louie" Zamperini in a scene from "Unbroken." (AP Photo/Universal Pictures)

But O’Connell became aware of the WWII drama’s potential impact on his career long before its release.

“I have spent a lot of time, since we wrapped on Unbroken, turning offers down — offers as a result of word of mouth, not necessarily a result of the work itself,’’ he says.

“So it’s a patience game now.

“There have been some really tempting offers — I could be sat here as a wealthy individual right now but I had to swerve in order to preserve my integrity as an actor.”

Among the projects O’Connell is hoping to green light is Money Monster, in which he would star opposite George Clooney. Julia Roberts is also in talks for the financial drama, to be directed by Jodie Foster.

“That’s feeling more real,’’ he says. “I have my sights set on it but I can’t confirm anything yet.”

In this image released by Universal Pictures, Jack O'Connell portrays Olympian and war hero Louis "Louie" Zamperini in a scene from "Unbroken." (AP Photo/Universal Pictures)

After Unbroken, he took a small role in Tulip Fever, with Alicia Vikander, Christoph Waltz, Holliday Granger and Judi Dench.

“This is the soppiest I have got on a cinema screen so far,’’ he admits.

Compared to Jolie’s film, the 17th Century romantic drama felt like a paid holiday.

“I just rocked up. I wasn’t playing the lead. I had enough meat on the bone to enjoy myself and feel like I had a purpose. I came away feeling a little bit rested,’’ he laughs.

Like Zamperini, O’Connell had his own flirtation with juvenile delinquency.

“I know where the line is — and I take a lot of pride in staying this side of right and wrong,’’ he says.

“The difference being that nowadays my life is actually good. I have opportunities now.

“When I didn’t I was restless. I wanted to maximise and enjoy myself and sometimes that meant stepping on other people’s toes.”

Jack O'Connell arrives at the National Board of Review Awards Gala at Cipriani 42nd Street on Tuesday, Jan. 6, 2015, in New York. (Photo by Evan Agostini/Invision/AP)

The actor says he started out at what felt like “rock bottom.”

“It was a lot of hard work. It was a drag. There were even times when I was a professional actor when my behaviour and my personal life weren’t necessarily in keeping with what I was trying to achieve as a professional.”

But now that he’s top of Hollywood’s “young actors to watch” list, O’Connell is quite happy to be boring.

“I like an early night these days — because shoots like Unbroken take it out of you.”

Unbroken opens in Australia on Thursday January 15.

Originally published as Unbroken star Jack O’Connell says his breakthrough role hurt as he survived on just 400 calories a day