'Grunt' tackles the science behind some of a soldier's most challenging adversaries -- panic, exhaustion, heat, noise -- and introduces us to the scientists who seek to conquer them. Mary Roach dodges hostile fire with the U.S. Marine Corps Paintball Team as part of a study on hearing loss and survivability in combat. She visits the fashion design studio of U.S. Army Natick Labs and learns why a zipper is a problem for a sniper. She visits a repurposed...

Platoon is the story of every soldier whose innocence was lost in the war-torn jungles of Vietnam. Chris Taylor arrives in Vietnam and quickly discovers that his worst enemies are not just the Viet Cong, but gnawing fear, physical exhaustion and the anger growing within himself.