Jack O'Connell responds to accusations that SAS Rogue Heroes glamorises violence

More recently, he found himself in the Moroccan desert for the first season of SAS Rogue Heroes, which the Derby-born actor admitted at the time was his most gruelling job to date. But, it seems, the 34-year-old is quite the glutton for punishment and so was pleased that the BBC series was recommissioned for another dose of daring SAS Second World War missions. The first season was set in 1941, during the North African desert campaign in which the misfit mob of brutally efficient soldiers was founded by Lieutenant David Stirling (Connor Swindells) and led from the front by O’Connell’s Lieutenant Paddy Mayne, an authority-hating, poetry-spouting Irishman. For season two the theatre of war moves to Europe, and the 1943 invasion of Sicily, which was a near-suicidal frontal assault led by the SAS.

This time there was no pre-production boot camp, a surprise given the brawny physicality that’s on display from O’Connell and co. "Maybe they considered us initiated... Either that or there were cutbacks!" he says with a laugh. Nor did he have to do as much research into the history of the SAS. "One of the major perks about developing Ben Macintyre’s book is we always have it," he says of the author’s non-fiction work of the same name, used by show creator Steven Knight (Peaky Blinders) as inspiration for the two seasons’ actual and imagined events. "It’s forensic in its detail, so we have that additional resource alongside the script."

So how did season two’s four-month shoot - in which Croatia stood in for Sicily - compare? "If any of us approached it expecting it to be a whole lot easier, there would have been a rude awakening," O’Connell says with a dry chuckle. "Although we weren’t in the desert, and we weren’t so cut off and remote, it was still hot."

The season begins in Cairo, kicks off with that terrifying seaborne Italian invasion, and then involves running battles with the Germans as well as the Mafia, so there was a lot to pack into six episodes. "This show is so ambitious, to get everything that we needed in the schedule was some task. So, you’ve got to be fit - physically and mentally. Because it is heavy, and it’s got to be because of the subject matter."

From the opening scene, we see the toll war takes on even the toughest of the tough. Mayne is refused permission to return to Ireland from Egypt for his father’s funeral and in his rage, takes out an entire snatch squad of Military Police. It was a feeling that O’Connell - who was born into a working-class family in Alvaston in Derbyshire and made his big screen debut, aged 15, in Shane Meadows’s This Is England - says he could relate to.

"Being away from home is probably the hardest part about this job," he admits. "Not seeing the people close to you, not being there for them... So, yes, that was easy to draw from."

How does he respond to the argument that, with its rock ’n’ roll soundtrack and macho, shoot-’em-up action, SAS Rogue Heroes glamorises violence? "I don’t know if I’ve got a counter-argument for that," O’Connell admits. "My stance is: this is an important period in history. The actions of these fellas are responsible for the liberty we have. That rise up against fascism is amazing to me. And if it glamorises violence in doing so, then... I don’t know," he concludes with an audible shrug.

He’s equally candid when I ask him why he’s drawn to such tough and often traumatic roles (see also his rage-filled young inmate in David Mackenzie’s powerful prison film Starred Up). "A casting director would be better equipped to answer that. But is it a comment on the type of roles available to a working-class actor?" he wonders. "I didn’t study acting, I didn’t go to Rada - I couldn’t afford to go to a drama school, like a good number of other actors can’t. The majority of people in this country can’t afford to go to those schools... So a lot of my career is about forging a path. It’s very rare that these opportunities get handed out, especially to an actor like myself. So maybe it’s to do with that."

Now, of course, O’Connell has his pick of roles. He’s recently filmed Danny Boyle’s zombie franchise-restarting 28 Years Later. He’s some kind of abominable antagonist in Sinners, a horror film from Ryan Coogler (Black Panther) that he shot in the summer in Louisiana. And earlier this year, in Amy Winehouse biopic Back to Black, he was Blake Fielder-Civil, a different kind of villain: the on/off boyfriend who arguably enabled the singer’s drug-addiction.

It’s a lot to shake off. Hence O’Connell’s multitasking today, talking up his new show just before hitting the gym. "I like to box," he says, readying for his training session. "I like to play football. Look after yourself, because you are your tool kit at the end of the day.

"That time in between the jobs," he adds, "you can either see it as a load of time off where you get fat and let your hair down, or you stay in tune and stay active for the next role."

Which will invariably soon see him jetting off to some extreme location for months on end, to film his next gruelling but glorious drama.

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SAS Rogue Heroes season 2 will air at 9pm on New Year's Day on BBC One and BBC iPlayer, while season 1 is available on BBC iPlayer now.

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