On 1917, production designer Dennis Gassner faced the monumental challenge of crafting epic World War I sets for a film that would appear as one take.

Based on stories told to director Sam Mendes by his grandfather, the thriller centers on Lance Corporals Schofield (George MacKay) and Blake (Dean-Charles Chapman), two young British soldiers that are given a mission to deliver a message deep within enemy territory. Racing against the clock, the pair put their lives on the line, knowing that the message they have to share may save the lives of 1,600—including that of Blake’s own brother.

Comprised of a handful of long takes stitched together to look like one, 1917 leads viewers to believe that the soldiers they’re watching are running from one set to another, laid out in some kind of linear fashion. In reality, though, the film was shot all over the U.K., and it fell to Gassner—as well as his fellow department heads—to reinforce Mendes’ masterful cinematic illusion.

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Even with extensive rehearsals and a thorough pre-production process, Gassner says the shoot was a race against time, much like the one that Schofield and Blake themselves experience. “[It’s] amazing that you actually get to see a film that is made like this,” the production designer says, “and I think nobody will ever get to do something like this again.”

Below, the seven-time Oscar nominee outlines his approach to the war epic, discussing all the challenges that were overcome, to realize one of the year’s most remarkable films.

DEADLINE: What were your first thoughts when Sam Mendes approached you for 1917?

DENNIS GASSNER: Every time I talk to Sam, it’s like I drop off into the abyss, and that’s why I like working with him, because he challenges himself and everybody that is involved in a project. This one was just an amazing project to solve problems, and the problems were obvious to us. It was that time was the enemy, and every aspect of that, because that permeates throughout the whole project. So, how do you go about doing it? We learned a little bit about this when we did the opening sequence of Spectre, which we wanted to appear like one shot, so there were some aspects of it that we were familiar with. But to sustain that over an hour and 58 minutes, how we manifested that was through arduous planning.

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What we ultimately had to do was plan it inch by inch. We put stakes in the ground. Sam read the script and walked, and started to run, and so it became simply that: How do you measure that time? This was a three- or four-month process, which continued along when George and Dean came on as our performers, and then everything changed, and changed, and changed. We drew everything in a plan, and then the physical nature of the movement was done physically, and then we built it and shot it. It was simply that.

I’m saying that flippantly, because it was not easy to do. Every step you took meant there was another challenge to face. But it’s my fifth film with Sam, and my ninth with Roger [Deakins, cinematographer], and we have a particular kind of shorthand of cutting to solving the problem. The problems were infinite, and daunting in every way, but we did it. I think the amount of experience that all of us had had together was the only reason it got done.

DEADLINE: What were your first impressions when you read the script? How did they inform your approach to designing the film?

GASSNER: When I read this, I read it as a dream state. It was such an old memory that Sam had, and I think that kind of permeated the script itself. So, I decided to approach it not with art being pretty art, art being the most accurate. Whatever we were going to be building had to have a quality of slightly heightened reality—a dream state or a surreal state—and just by design, that’s coming from an emotional state of mind. So, that was the approach in the art department. I think in the end, the collective of all the environments you saw had this strange, kind of surreal quality to it.

DEADLINE: Part of what’s so remarkable about 1917 is its ability to convince viewers that they’re viewing one continuous experience, occurring within one continuous environment, when really, the series consisted of a handful of takes, shot at a series of disparate locations.How did you work with Mendes to pull this trick off?



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GASSNER: Well, you could only go as far as the landscape would allow you. [We had to] find places that would allow you to dig a trench, and don’t have archeological sites, and in fact, we faced that all the time, in the last locations in Salisbury. It was always about the look, first of all. How did the look in the environment feel? What was the color of the dirt that we were going to be in? Because the color of the mud was going to be integral to how the movie felt, emotionally.

We tried to find spaces that could allow us to do exactly what we needed, and it was a long process of finding all these elements. Then, you take all these elements and start to piece them together in drawings and models, and all of these things start to come together eventually. All that work of planning and stitching together allows us to then say, “Here’s our plan. Here’s our blend points, how the blend points work, and transitions of camera.”

Then, the other thing that was the most difficult actually [was the weather]. Luckily, we were in England, and England generally has an overcast environment, but there were still times that we had to wait for the clouds, wait for non-sunlight. This whole thing was based on Sam’s grandfather’s stories, and we always kind of said, “Granddad’s watching over us today.”

DEADLINE: When you say you worked out the choreography for the film inch by inch, what exactly did that look like? What kinds of steps did you go through to perfect the timing of each shot?

GASSNER: You start out in a field that’s not even going to be the field that you’re going to be doing the digging in, just to get the timing right. Then, you have to find the place that you’re actually going to do that, and then you have to do it again to make sure it’s right. Then, you have to see if we can actually do the digging, and it’s ongoing all the time. I had six art directors, and I gave them three or four sets each to do. So, I master planned everything, and then everybody was working tirelessly to try and figure out what the problems were, and present the problems, and then we had to find all the solutions. With all that, the clock was ticking. We had a short time to do it and a release date of December 25th, and it was like a constant train wreck that we actually got through.

DEADLINE: You dug almost a mile of trenches for the film. What was that process like?

François Duhamel/Universal Pictures

GASSNER: Well, we built it the way they would have built it [during World War I], and we had the same problems that they had. We had weather problems, we had three feet of snow, we had torrential rain, we had floods. We had to keep re-digging. I mean, it was the war, because nothing really has changed since then. We’re in the same kind of environment, and we’re in the winter, trying to protect ourselves, and we’re trying to make a movie about it. So, it was hard work. I’ve done this for 40 years, but this was really, really hard work.

DEADLINE: One of the film’s most remarkable sequences takes place in the ruins of a cathedral, which is lit by flares as Schofield runs for his life. What informed your designs for that structure?

GASSNER: That was very loosely based on Écoust, a town in France, and again, the same process applied. We had to lay it out inch by inch, but we had to design the entire city, what the reality of it was. Then, we had to break it down. So, all of our working drawings were the realistic part of the building, and then we had to take it apart, brick by brick, to manifest the effects of war.

DEADLINE: Sam Mendes needed to be able to shoot freely in 360 degrees on this film. What was it that made that possible?

GASSNER: It was a lot of information, and it was always also the planning of how the camera was going to work. We knew where the camera was going to be, where it was going to turn, where it was going to pivot, where we were going to do all that, so we had to then design for that movement and put architecture there—in this case [the ruins], for George to run through.

DEADLINE: Apart from the trenches and the cathedral, which were some of the most challenging sets to design?

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GASSNER: Well, every one. There was not one that had a weak spot in it. Nothing was easy, let’s put it that way. You know, there was hard, and then there was really hard, and then there was impossible, and then there was beyond impossible, based on time, weather and conditions. Here’s just a little example. When we [were on] a piece of land in England of great history, you had to have an archeological study done to make sure that when we dug under the ground, there would be nothing historic, like some underground Stonehenge. So, everything took time, and multiply that by 60 or 70 sets. You can just imagine the time pressure before we could even dig the trench, and then we had to dig the trench.

DEADLINE: You’ve designed a lot of epic films in your career—Skyfall, Spectre, and Blade Runner 2049, among them. How did 1917 compare, in terms of degree of difficulty?

GASSNER: They’re all difficult, but [on] this one, you were out in the elements all the time. You know, I’ve been in burning deserts and frozen environments, [but] this was English weather. It’s damp, it’s cold, it’s wet, it kind of gets into your bones, and it’s just one of those things that you accept. You keep pushing forward, and as a group, as in the war, you keep fighting. And that was the beauty of the experience, in some way.