You’ve never seen a war movie quite like “Journey’s End,” taking place on the frontlines of France towards the end of World War I. This doesn’t necessarily mean variations on the explosions the mind might immediately conjure, though there are certainly some on display, but rather the exposure of far deeper ruptures within the soul as civilians-turned-soldiers are compelled into action by a sense of duty to country but uncertain of what carrying that duty actually means when their lives have not prepared them for such circumstances.

Based on R.C. Sherriff’s play written a decade removed from the time it’s set in the spring of 1918, the film version is unlocked from both its time and stage-friendly setting inside a dugout by the modern dynamics introduced by screenwriter Simon Reade and director Saul Dibb, who after making historical dramas “The Duchess” and ‎”Suite Francaise” has become an old hand at refreshing period pieces. Armed with a cast that includes Paul Bettany, Sam Claflin, Tom Sturridge and Asa Butterfield in the C-Company that we embed with for six days in the trenches, “Journey’s End” acknowledges from the start that their mission is futile, but the desire to find meaning in it is not as they wage a more internal conflict of putting on a strong face at death’s door or opening up to each other about their fears‎ to make the end not feel so lonely. Running the gamut in age and rank from Butterfield’s eager young grunt to Claflin’s increasingly distressed Captain Stanhope, who’s charged with leading his men into a surprise daylight raid, the men’s loyalty to each other is informed not by personal attachment to one another, but by their experiences off the battlefield as much as on it, with the soldiers showing great consideration for what to say or do to fortify the front as a human endeavor, even if it’s looking quite porous as a physical defense.

With sleek camerawork guiding one throughout the muddy tunnels of the platoon’s barracks, “Journey’s End” keep pulses racing as much for tracking the fluid emotions of the troop as much the constant threat of bombardment, allowing for moments of great gentility as well as mischievous humor since no one ever quite knows what the cook (played by Toby Jones) is putting in the soup. But the same can’t be said for Dibb, who makes quite a rich stew out of the disparate array of characters he has onhand for a fraught situation and shortly before the film’s premiere at the Toronto Film Festival, he spoke about how he helped create an atmosphere on set that let life into the film, embracing certain limitations of the film’s scenario and making a piece of history feel current.

Asa Butterfield in "Journey's End"How did this come about?

It was the most straightforward film I’ve ever done in a way. I was finishing another film when I was sent the script, and I thought that it had this amazing ring of truth to it and [that] we could do some simple things to it to really open up what I felt was there in terms of its potential and make something that was very powerful, very human, but not in any way sentimental or glorifying of war. So I pitched my version of what I wanted to do to Simon [Reade], the writer and producer, and Guy [de Beaujeu], the producer, and in the meeting, they said, “Yeah, great, let’s make it.” [laughs]

Given the limited locations, did you immediately see the cinema in this?

I saw the potential for it. The characters and the situation were incredibly powerful, but probably was a bit talky and I felt that what we wanted to do dramatically was not reveal what was going to happen in the final reel. We wanted to put that upfront — put the bomb under the bed essentially that these are 120 dead men walking, so there would be a terrible sense of dread, and it’s not [a question of] if, it’s when. For things to work cinematically, it’s not just about the visual elements. It’s about storytelling and tension, and I felt was there was a chance to do something cinematic out of the very opposite of what people think cinema is by confining the visual landscape, by limiting the point of view throughout the film, and that we would be able to create something that was distinct because of those limitations, not despite them.

I’ve long admired how you’ve made these historical dramas that feel so immediate – are there certain things you abide by in unlocking the story from the time its set in?

Point of view is key – to assume a very clear point of view that’s very close to the characters. We’re not making it objectively from a distance. It’s about trying to create an intimacy with these people and shooting in a style that allows the performances to feel very real, natural and underplayed. And also doing things like not lighting it and using the best modern technology has [to offer] . With these extraordinarily sensitive new cameras, it means we could shoot the whole of the dugout scenes all by candlelight for real or trying to find a nontraditional way of scoring a film, like finding a crazy experimental Icelandic cellist that we got to do the music, those maybe more modern approaches to making a film.

Sam Claflin in "Journey's End"This may have been inherent in the script, but with a testosterone-heavy set, there’s a lot of gentility in what comes out onscreen. Was there any secret to fostering that environment?

Yeah, there is that kind of testosterone thing with all these men together, but what I find very powerful about it is all these men are hiding their fears in front of each other and deflecting it all – talking about food and all of that kind of stuff. We were just very lucky with the actors that we had and it’s top-down. You create an atmosphere on set where you’re clear with everyone on the kind of film you want to make and then you pick the actors that you want who you think will all fit together and [this is] a testament to them. Sometimes you get a group of actors together and they don’t gel and with this, they all gelled and respected each other.

[In terms of casting] you begin with central characters really and move your way out. Paul Bettany is a brilliant actor who I haven’t seen in British films for a while, so it was very exciting to have him and Sam [Claflin] as well, who clearly is massively on the up, and Asa, who is a 19-year-old young man who was able to make this film as the age of the character, which was very important. But what I also really loved about it is that there is a cast of brilliant but usual suspects for a British film like this and we didn’t cast any of those people. We cast a completely different constellation of characters to come together in the film.

Toby Jones seems like a particularly inspired choice.

Yeah, he’s superb and it’s not necessarily the kind of role you’d expect him to play, but once he plays it, the added value that someone like Toby can bring to that part, it feels much bigger than it was on the page or might’ve been in somebody else’s hands. Suddenly, he becomes absolutely crucial to the whole piece and what he can do with a kind of grunt or a murmur or a look might take another actor three or four scenes to deliver that kind of information. He’s also incredibly funny and clever.

Was there a particularly crazy day of shooting on this?

To be honest, most of them were. We shot the whole thing in six weeks. It was a very tight schedule, and the raid was very intense because we were asking everyone to do it for real. We rigged explosives ahead of everybody, so as you see in the film, they’re running towards these enormous explosions and we were shooting whole takes of them running across, so you had that proper sense of exhaustion and desperation and them covered in mud. You’re asking a lot of your actors to do that again and then again and again.

Sam Claflin in "Journey's End"What was it like to build those trenches?

We dug them out of the ground and we said, we’re going to build a network and film in this real network [with] whatever weather is thrown at us in the shooting period because that’s the way they would’ve had it. So we’d harness the things [we] had available to us as filmmakers — the light in the sky, what it’s like in the morning, following the rhythms of the day essentially to allow it to mirror the real experiences as much as possible.

With a war film, were you also able to go nuts on the sound design for this because you can get all those layers in?

That was really important. What we wanted to convey was the experience of being there, so you could do that visually, but the sound of the whistling wind, the distant guns, and the squelching mud under their feet, it’s making sure that you catch all of that stuff and in the action sequences, we have to have them as detailed, as violent and as real as possible.

Were you actually able to shoot at least the dugout scenes in chronological order?

We shot it in two chunks — all the [exterior] scenes chronologically, and then we went inside and shot all of [the dugout scenes] chronologically, so that actually worked out in a very productive way [because] as much as I think you can do things chronologically and mirror [the experience], especially when you’re looking at how relationships and people are breaking down, it was really helpful to be able to do that. And our last shot of the whole shoot was us blowing up the bunker, so by the end of it, there was nothing else we could do. [laughs] We all had to go home.

“Journey’s End” does not yet have U.S. distribution. It will open in the UK in February 2018.