Cosmo Jarvis on Warfare: ‘No other film will ever push me this far’

Cosmo Jarvis went from drawing samurai swords as the hero of Shogun to playing an American sniper in Warfare. It took him to his limit.

Actors Cosmo Jarvis (R) and Taylor John Smith on the set of Warfare, 2024. Picture: Murray Close/Getty Images.

‘You’ll get Cosmo,” the rep for Cosmo Jarvis says before our interview, “but a bit posher than normal.” The Devon-raised actor likes to stay in the accent he is using for a project when off set and – since he is playing a plummy Brit opposite Anthony Hopkins in Guy Ritchie’s forthcoming aristocratic movie Wife & Dog – that means I get plummy Jarvis.

It’s not just the accent but the phraseology. At the end of a chat in which he has been courteous yet at times anguished, he says solemnly: “I wish you good luck in your onward journey.”

This is confusing because we are at this central London hotel to talk about another film, the blistering Warfare, in which he plays an American soldier in the Iraq war and speaks in an inch-perfect Illinois drawl. Jarvis, 35, has done this for a while, he says, conducting day-to-day life in a Northumbrian brogue for his breakthrough role as Florence Pugh’s farmhand lover in Lady Macbeth; an Irish lilt when playing a gang enforcer in Calm with Horses; and a New York drawl for his fat-suited mobster with Robert De Niro in the recent Alto Knights.

He is best known for another plummy character, an Englishman in 17th-century Japan, in Shogun, Disney’s hit television series, and heaven knows what accent he will come up with when he appears in Christopher Nolan’s version of Homer’s Odyssey, opposite Matt Damon and Zendaya in an as-yet-unnamed part. Jarvis is so adept at vocal camouflage that it’s not immediately obvious what his real voice sounds like.

What doesn’t change is the intensity of Jarvis’s performances, which mix muscularity and vulnerability like a young Richard Burton or Oliver Reed. Does he get that a lot? “People have named all kinds of names – Michael Palin,” he says. That’s a stretch, although he may have a touch of Palin’s sergeant-major in Monty Python. Jarvis is the type of actor – often smaller in person than you expect – who throws everything into their performances but hates explaining them. “I don’t like talking about method too much,” he says. “It’s irrelevant to the final result. I do the most (preparation) that I can in order to forget (when on camera). It takes a while to find the person and then you stay with them until it’s done.”

Warfare was right up his street, a re-creation of a special forces operation in Ramadi in 2006 that has been called the most realistic war film in history.

Co-directed by Alex Garland, who made Ex Machina and Civil War, and Ray Mendoza, a former US Navy SEAL who was part of the original mission, it is told in real time and with a deliberate lack of glamorisation. “It didn’t care for dramatic convention or anything that didn’t originate from the event,” Jarvis says.

Before the shoot the actors shaved each other’s heads (“some of them did”, Jarvis says) and went on a boot camp where they were taught about weapons and tactics and set brutal endurance tests.

“No other film will push you this far,” Jarvis said to himself at the time. “You think, I can’t do it any more, but what Ray cleverly did is instil in us that any such limitations can be overcome by ­shutting up that part of you that feels tired and weak and ­dehydrated.”

Jarvis as John Blackthorne in Shogun Picture: FX

Jarvis’s co-stars referred to him by his character’s nickname, Booger Boo, and on-set communication replicated the chain of command, with the directors speaking only to the actors playing senior officers, including British actor Will Poulter, who passed instructions down. “That was a stroke of genius on Ray’s part,” Jarvis says.

The start of the film, in which the team is installed in a house across the road from a suspected den of Iraqi insurgents, is low key to the point of tedium. While his comrades do push-ups and take the mickey out of a recent recruit for his “new guy energy”, Jarvis’s sniper, Elliott Miller – Warfare is dedicated to him – lies on sofa cushions, trains his sight on the building opposite and gives a colleague a forbidding stare modelled on what Mendoza called Miller’s “Neanderthal face”.

Jarvis says: “Elliott was an incredibly competent sniper and medic but also a funny guy.” Suddenly everything erupts: explosions, firefights, airstrikes and wince-inducing shrapnel injuries to two men. There is smoke, confusion and a lot of convincing groaning. Several of Mendoza’s former comrades were on set, Jarvis says.

“If any of those guys made a comment the whole group took that direction, so all of them got to be directors.”

Miller was among them. “If he wasn’t buying the emotion of guys seeing that their brothers have been obliterated he would say so. The only thing he said to me was, ‘Don’t f..k it up.’ These guys aren’t overly sentimental.”

Jarvis with Vincent Miller in Inside.

The cast felt the pressure of playing real people.

“There was a feeling of the stakes being higher than making entertainment,” Jarvis says. It must have made him wonder how he would fare in combat. “They’d never let me in. I’m diabetic so I wouldn’t get past the physical.” The film avoids judgment on the Iraq war, as does Jarvis. “My opinions are irrelevant. This is a film about a bunch of men on a street in Ramadi and a very specific thing that happened. That’s all it’s about.”

Jarvis grew up in Totnes with his Armenian-American mother and British father but doesn’t want to go into his childhood.

“Places are irrelevant,” he says. “There are people and things you do.” He is equally evasive about an early musical career that included Gay Pirates, a folk ditty from 2011 that has been streamed more than three million times. He once suggested that he used music as a springboard to acting but squirms at that now. “Music was just something I used to do.” He lives in London with his wife and baby daughter. “I like the idea that I’m working for these people now.”

Jarvis also stars in the forthcoming film Wife & Dog.

The thing people ask him about most is Shogun, which won four Emmys last year, including outstanding drama series. Shot in Vancouver, it stars Jarvis as seafarer John Blackthorne (played by Richard Chamberlain in the 1980 miniseries) who rises to become a samurai under Hiroyuki Sanada’s Toranaga, the would-be lord of the title. Some have compared Britain and Japan, two emotionally repressed island nations. “Possibly. I will say that Japan is cleaner,” Jarvis says.

Shogun went down well with critics there – did he get any feedback when he visited on a promo tour? “None that I could understand.” He can’t speak the language and learnt John’s occasional rudimentary dialogue phonetically. “We just didn’t want to disappoint them,” he says.

Toranaga is based on a real person, Tokugawa Ieyasu, and to muck it up would have been like making “some bastardised piece of pseudo-historical content based on a beloved British figure”.

He has signed up for the second season, which will tell a story beyond James Clavell’s novel. “They are aware of the responsibility in departing from such a tirelessly researched source.”

Before that there is Nolan’s Odyssey (“I was a big fan of The Prestige”). Already released is Inside, an Australian prison film in which he plays a rapist “finding salvation through God”. Plus that Ritchie movie, which is why, as we say goodbye, Jarvis is still speaking like a High Court judge.

The Times

Warfare is in cinemas.