During the Vietnam War, the Que Son Valley region was a very bad place with a very bad reputation. More U.S. Army infantrymen and Marines died there than at any other location in Vietnam. More Medals of Honor were awarded in this region than in any other single combat zone, ever.

On 5 May 1968, the downing of two U.S. helicopters in the Que Son Valley marked the beginning of the North Vietnamese Army's second Tet offensive, with the goal of destroying all U.S. forces. At 1728 hours, Delta Company, 1st Battalion, 20th Infantry conducted a combat air assault to join Bravo Company, 1st Battalion, 6th Infantry at the helicopters' fatally downed location.

Their experiences during the next six days set the stage for a three-month long battle that lasted only hours for some. In the end, there would be more than 2,300 dead and wounded, and one American Soldier missing in action. It will take over 44 years to find his location; UNACCOUNTED is his story.