I recently saw the documentary They Shall Not Grow Old, an account by English soldiers of their experiences in the Great War of 1914-1918. Culled from hundreds of hours of colorized actual wartime footage, it's a beautiful and heart wrenching film. It's also a superb antiwar film, simply through its graphic and accurate depiction of mass death and casualties across blood-soaked European battlefields.

Refreshingly, the film relies solely on audio transcripts from about 200 English soldiers who fought in World War I. There is no script, and no narration. The viewer simply hears the gravelly, aged voices of the soldiers themselves, never identified by name or rank. They are anonymous, but judging by the towns from which they hailed and the farm or factory jobs they left, most were enlisted men.

Though commissioned by the BBC, producer Sir Peter Robert Jackson has no political axe to grind. This is a story of men, of human beings and their oftentimes horrific experiences in perhaps the savagest of modern wars. It has little to say about particular battles, commanding officers, politicians, or any of the events surrounding the war. It stands apart from most war documentaries precisely because Jackson strenuously avoids any filter between the soldiers' recollections and the viewer.

From the outset we see the naivete of young men, many no more than 15 or 16. They hear vague rumors about the assassination of Franz Ferdinand. They see activity in their small towns and villages, with soldiers bustling about setting up enlistment stations. They read newspaper reports about Germany threatening Europe, and feel both pressure and pride compelling them to join the war effort. Though the official enlistment age is 19, many of the taller boys lie and are readily accepted.

For almost all of them, signing up is simply the thing to do. They join the fight for their mates, for their families, and for the approval of the girls and older people in their towns. Still teenage boys, they have no capacity to imagine or justify what will come. Questions of politics and ideology, questions about just or unjust war, are simply outside of their thinking at the time. Joining the war, and defending England, are obviously the right thing to do.

Training is scant, and often local. A few older men in their 30s and 40s with military experience set up barracks and begin teaching basic formations and physical fitness. Quartermasters dole out ill-fitting uniforms and stiff boots, all fated to become rotted and waterlogged in trenches. Well-used Enfield rifles are issued, heavy and quite foreign to many of the boys who have never fired a gun. And after just a few weeks, the boys head off to the beaches, woods, and fields of France, Germany, Prussia, Belgium, and beyond—scarcely removed from their school boy or farm boy days. Anyone with a young teenager can imagine how their parents felt.

The battle scenes are gruesome, and intense. The film does not spare viewers. Dead and dismembered bodies feature frequently, but the sheer horror and bloodshed are moving rather than gratuitous. Humanity in wartime isn't an abstraction, but the real and abject collection of flesh, bone, organs, blood, and tissue of the soldiers who were running beside you a moment ago. War is violence, and They Shall Not Grow Old never strays from reality.

Motorized military transport was less common then, so horses were ubiquitous among officers. But the equines too are slaughtered, and some post-battle scenes show a staggering number of dead and injured horses, some still braying and flopping in misery.