Watch Sebastian Junger's 'Korengal' Trailer

In a unique collaboration with "Nightline" and Vanity Fair, writer/director Sebastian Junger and the late photo-journalist Tim Hetherington followed one platoon from the 173rd Airborne in the Korengal Valley, one of the deadliest outposts in Afghanistan, in 2007.

First aired in a "Nightline" special called "The Other War," the project led to Junger/Hetherington's Oscar-nominated documentary, " Restrepo," and later to "Which Way Is The Frontline From Here," a homage to Hetherington following his 2011 death in Libya.

Junger's next chapter, " Korengal," picks up where "Restrepo" left off.

"'Restrepo' was intended to be a way for civilians to experience what combat feels like. 'Korengal' is very different. It tries for understanding rather than experience. How does fear work? Courage? What is it like to come home from war? Why do so many soldiers miss the war they were in?" Junger said in a statement.

ABC's Chief Investigative Correspondent Brian Ross will interview Junger in an upcoming Memorial Day special report to air on "Nightline" on Monday, May 26.

"Korengal" will be released on May 30. Watch a sneak peek of the film in the newly-released trailer: