Synopsis: Prepare for a stunning, no holds barred journey into the darkest chapter of the Vietnam War. A special U.S. combat unit trained in underground warfare is sent on a mission to hunt and kill Viet Cong resistance forces in the endless networks of tunnels in the jungles of Ch Chi. Armed with only handguns, flashlights and knives the men soon find themselves embroiled in hand-to-hand combat. The Vietnamese that inhabit the tunnels are faced with an equally overwhelming task. By restoring to primitive but ingenious methods of combat, they prove to be surprisingly effective against the Americans' superior technology. As the battle moves underground, for both sides, struggle becomes less about winning than about survival.