The old saying goes that, “war is long periods of tedium punctuated by moments of sheer terror.” No film in recent memory captures that contrast with more crystalline ferocity than They Shall Not Grow Old. In the hands of Peter Jackson, this documentary never feels like a simple remastering or a coloring of the past with crayons. Instead, Jackson fleshes out the Great War in three full dimensions of adrenaline and blood-soaked horror. Those who only know this crucial period of history through rickety, clattering silent footage will be staggered by what they see here.

Jackson wisely eschews clunky narration in favor of archival anecdotes from the troops themselves. These Tommies recount their individual experiences with everything from casual detachment to sweeping nostalgia and finally aching heartbreak and regret. Basic training brims with a sense of whimsy and adventure, like boys off to camp. One private remembers an urge to taste a little combat before the whole thing is over. He and his fellow infantrymen soon feel the piercing brutality of trench warfare, a maddening combination of tension-filled anticipation and bayonet-tipped savagery.

The digital wizardry on display here feels comprehensive and invisible at the same time. 3D rendering is done with such painstaking precision that it eventually becomes completely natural and immersive. Foley is layered throughout the speakers, so that Western Front comes alive with booming artillery, shrieking horses, and clunking tanks. For all this meticulous attention to color and cacophony, everything takes a back seat to the gripping recollections of the troops themselves.

A stark irony of the First World War is that many of the men who waged it cared little about entangling alliances or aristocratic blood feuds. Many still were not even men: Hundreds of thousands of teenagers volunteered, only to fill the trenches with their bullet-ridden corpses. They Shall Not Grow Old tells the story of those who would never get the chance to grow old and many more who would grow old before their time. This is a film that must be seen, preferably on the big screen.