Warner Bros.

What immediately stands out in Peter Jackson’s documentary They Shall Not Grow Old is the faces of its subjects. A painstaking restoration of century-old video footage from the First World War, the film is a complex project with a simple goal: to try to convey what it was like to live and fight on the Western Front from 1914 to 1918. But the technology Jackson deploys is so advanced that the documentary, which has been colorized and enhanced, captures a surprising degree of character and realism. The British soldiers’ faces smile, wrinkle, and grimace—all without the artificial, sped-up look typical of archival cinema.

“You recognize the minutiae of being a human being; it suddenly comes into sharp focus,” Jackson said in an interview with The Atlantic about how his film—quite literally—offers a different way of seeing the men who fought in World War I. “You realize, for 100 years, we’ve seen these guys at a super-fast speed, full of grain, jerky, jumping up and down, which has completely disguised their humanity.” In creating They Shall Not Grow Old, a five-year process carried out in tandem with the British Imperial War Museums and the BBC, Jackson tried to emphasize that personal touch, crafting a documentary experience that’s far more immersive and tactile than most.

Though They Shall Not Grow Old has already aired on British television, it is best seen in a theater—it will play limited special engagements in North America on December 27. The film is being screened with eerily impressive 3-D projection that adds an extra layer of verisimilitude, but to Jackson these added presentation elements aren’t the main draw. More significant is the restoration itself, which was completed by his company WingNut Films, the main force behind his effects-driven Lord of the Rings and Hobbit movies. (An American company called Stereo D did the colorization and 3-D conversion for They Shall Not Grow Old.)

When the Imperial War Museums first contacted Jackson and handed him 100 hours of raw footage, it asked only that the video be presented to audiences in a “fresh and original way,” without any new material from the modern era. Unsure at first how to translate those instructions into a full-fledged documentary, Jackson began by tackling the restoration. During World War I, footage was shot on hand-cranked, black-and-white cameras, usually at 10 to 12 frames per second, which creates an “over-cranked” (or sped-up) visual when the film is played at the 24-frames-per-second standard of modern cinema.

“I set about doing four or five months of testing with a little piece of film that [the Imperial War Museums] sent, and I was amazed at the results,” Jackson said. “It was so sharp and so clear, it looked like it was shot now. It was way better than I ever dreamt it could be.” The director and his team carefully filled in the frame gaps, removed damage from the footage, and hired lip-readers to discern what people were saying so that dialogue could be dubbed in along with sound effects. “To me, the colorizing is the icing on the cake,” Jackson said. “But the transformation happens when you take away all that damage and get [the soldiers] moving at a normal human speed. They become real people again.”

Only after beginning the restoration did Jackson hit upon the idea for the documentary’s unique presentation: The film would focus exclusively on the trench warfare of the Western Front, and it would be narrated only by audio interviews conducted in the 1960s and ’70s with British soldiers who fought on those battlefields. “[Our goal] really became, at that point: We’ve got to show the war as the soldiers saw it,” Jackson said.

They Shall Not Grow Old doesn’t try to encompass every aspect of the massive conflict that was World War I, avoiding the potted-history approach of many documentaries. “I didn’t want to impose my own ideas on [the film]. I wanted to listen to everything on the audio interviews, to look at all the footage, and to let that find its own shape,” Jackson said. “To be quite honest,” he added, “the 100 hours of footage could make up seven or eight entirely different films.” So he ended up setting aside material about the air force, the naval battles, the women-led efforts in U.K. factories, and farther-flung engagements such as the Gallipoli campaign, knowing he wouldn’t be able to do them justice with one film.

Jackson was thus able to take a more slice-of-life approach to his subjects. “The mundane parts of being on the Western Front are the most interesting. These soldiers, they couldn’t talk about the history of the First World War, they couldn’t talk about the strategy and tactics,” he said. “There’s one guy who says [in an interview], ‘All we knew is what we could see in front of our eyes. Everything else, to the left, to the right, we had no clue.’ That myopic, super-detailed … view became the story that I should tell. It’s a story you don’t often see in the history books and the documentaries. It’s what they ate, how they slept, how they went to the loo, what the rats and lice were like. The comradeship, the friendship.”

The film begins with soldiers recalling what it was like signing up for the war (and acknowledging their limited understanding of the conflict), going through basic training, living in the trenches, and going “over the top” into the nightmare of no man’s land. As a sort of oral history with expressive visuals, They Shall Not Grow Old succeeds at putting the viewer into the middle of a distant period. I was personally taken aback by the profound sense of camaraderie on display, by the grins on people’s faces despite the bleak surroundings, and by the genuine compassion that many British soldiers expressed for their German counterparts.

“You listen to these guys, and you realize they don’t consider themselves to be the victims that we have turned them into,” Jackson said of the film’s subjects. “They don’t want our pity; they don’t feel self-pity. They were there, they chose to be there, they made the best of it, and for some of them it was a period of intense excitement … Some of them even thought it was fun. That surprised me.”

Still, the film doesn’t hold back in its depiction of the brutality of trench combat, and how most British soldiers started seeing the war as a pointless effort the longer it dragged on. “The strongest opinion they would have had was, ‘The German army’s in Belgium and France, and we’re coming over here to push them out because we’re friends [with Belgium and France],’” Jackson said. “I don’t think people could quite get their heads around why the British and the Germans were suddenly enemies.” As the conflict winds down and more prisoners of war are taken, testimonial after testimonial in They Shall Not Grow Old suggests that British soldiers saw little difference between themselves and their supposed adversaries.

“They were dealing with the same hardships, eating the same crappy food, in the same freezing conditions, and they felt a sort of empathy,” Jackson said. “They were there because their governments told them to be there.” That empathy, mixed with a sense of futility, is what makes They Shall Not Grow Old such a precise triumph. Jackson takes whatever amorphous ideas the average viewer might have about the First World War and uses real human experience to give them shape. As the film’s hundred-year-old footage springs to life, each face—whether muddied, wearied, relieved, or overjoyed—suddenly belongs to a recognizable person again. It’s both thrilling and humbling to witness.

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