The Enemy Within: The inside story of Eddie Routh, the man accused of killing legendary "American Sniper" Chris Kyle

Journalist Laura Beil recounts the tragic inside story of Eddie Routh, the Iraq war veteran and PTSD patient charged with killing American Sniper author and legendary Navy SEAL Chris Kyle and another man at a remote shooting range in Texas in 2013.

Kyle was considered the most lethal sniper in American military history, a reputation that earned him the name "the Devil of Ramadi" during his tours of duty in Iraq. His story became a New York Times bestselling autobiography. Following his military career, Kyle attempted to give back by counseling troubled veterans. This goal brought Kyle, his friend Chad Littlefield, and Routh together with firearms in early February 2013, when tragedy struck.

In exclusive interviews with the Routh family and others conducted prior to a Texas judge's gag order issued in July 2013, Beil pieces together Routh's history of mental illness as he moved through a Veterans Health Administration system struggling to meet demand for Post Traumatic Stress Disorder care, brought on in part by a decade of war. The Enemy Within is a reexamination of a hero's tragic death and the life of a troubled young marine.