A central question Sebastian Junger wanted to answer in his documentary Korengal was: Why do men miss war? The soldiers explain themselves.

Now in limited release, Korengal, directed by Sebastian Junger, is the followup to his critically acclaimed documentary Restrepo (2010). Both focus on the soldiers of the Battle Company of the 173rd Airborne Brigade Combat Team stationed at KOP Restrepo in the Korengal Valley, a remote area in eastern Afghanistan. For Korengal Junger recast hundreds of hours of footage that never made it into the original to create a companion film that is something new entirely.

Restrepo was a triumph, an apolitical look at the front of the war in Afghanistan, where soldiers far from the safety of a base and far from comforts like running water and phone communications, fought for an inhospitable six-mile hollow called the Valley of Death.

Junger captured the footage for Restrepo over a year, in 2007 and 2008, with photographer and Vanity Fair contributor Tim Hetherington. Restrepo went on to win its category at Sundance and was then nominated for an Academy Award for best documentary feature, in 2011. That spring, Hetherington was killed while covering the conflict in Libya. As a result, Junger stopped traveling to war zones, something he had done for nearly two decades, including many times for Vanity Fair.

“One of those things I wanted to answer [in Korengal] was: Why do soldiers miss war? If war is so horrible, and it is horrible, why do they miss it? What is it exactly that they’re missing that they don’t think they can get back in society? The short answer, of course, is brotherhood,” says Junger, “the extremely close connection to 20 or 30 other people who are all interdependent on one another. It’s an ancient human experience. I think we’re wired for it. I think it’s a product of our evolution. And when soldiers experience it, they don’t want to give it up.”

Though Korengal and Restrepo use the same format—instead of a narrator, tight shots of soldiers in front of a black background are used to tell the story—the documentaries are dissimilar in their content. Where Restrepo is more narrative-based, about the war in Afghanistan as much as it is about the soldiers at the furthest frontline, Korengal is more abstract, about the idea of war and its many consequences.