The Belfast-set historical thriller " '71" follows a novice English soldier running through midnight alleys as Northern Ireland erupts in sectarian ferocity. Its story of brutalized warriors lost overseas recalls Jack O'Connell's lead in Angelina Jolie's harrowing World War II epic "Unbroken."

In each film the 25-year-old star delivers a well-honed performance with terse speech, creating a compelling character through expression, gesture and body language.

"A lot of people need dialogue as a crutch," said first-time filmmaker Yann Demange, who won best director at this winter's British Independent Film Awards. "He's at a time and place in his life where it just clicked and that wasn't me directing. It's just one of those moments you capture."

The British Independent Film Awards agreed, nominating O'Connell as best actor against veteran powerhouses Benedict Cumberbatch, Timothy Spall and Brendan Gleason.

Demange was speaking at the Sundance Film Festival while O'Connell was patched in by phone from New York City, where he was being directed by Jodie Foster opposite George Clooney in the kidnapping drama "Money Monster." His next high-profile Hollywood role will be as the lead in Terry Gilliam's legendarily long-gestating fantasy "The Man Who Killed Don Quixote."

O'Connell praised Demange's powerful interpretation of an era when paramilitary Protestants hated Catholics, zealots detested moderates, and even the peacekeeping British had their share of undercover death squads. Rather than creating a period piece or turning the conflict into a tale of Iraq-by-proxy, "what he's done is made a very universally applicable film set within the parameters of war. Very sensitively, I feel."

"It's universal because ultimately we all know it's wrong," said Demange, who calls his film " 'Apocalypto' in Belfast," a nod to Mel Gibson's savage 2006 Yucatán chase movie.

"It's a pattern we see recurring," he said. "This reminds me of images from Beirut, of children, kids. Look at pictures of Ireland in that point and it's always a child somewhere looking through a window. It's a motif, because no kid should have to grow up in that. No kid.

"The extinguishing of every life matters in a film like this. I've done a zombie satire piece for television and that's like 'Pump more blood!' But that's something else there. Here, it has a responsibility."

Though "Unbroken" was based on the memoir of WWII veteran Louis Zamperini while " '71" follows a fictional story line, each is deeply somber, O'Connell said.

"In Angelina's case, she heard the World War II stories and found it important to honor the suffering they endured by depicting it fairly. I think Yann had the same approach. I think he became quite an expert on our particular area of conflict. I'm quite clued up on the history because I'm half Irish Catholic."

While " '71" shows military war crimes, "I'm not anti-army per se," said Demange, who came to London with his immigrant Algerian and French parents. "I had a brother that was in the army — special forces. I can see the band of brotherhood and understand that. But it's not the Second World War anymore. It's not like a clear enemy and fighting on the beach, it's these messy dirty conflicts where no one really knows the truth.

"We've lost lives and no one can really look a parent in the eye and explain why. That's not cool."