A lance corporal collapses and dies on an obstacle course at the Marine Corps Base, Quantico, Virginia; Gibbs and company investigate; Duck and the others see numerous wounds (as though from beatings) on the body. While Vance remains on leave, he makes some discoveries. Gibbs and Ducky learn separately about the victim's history of fighting; the gang determine the nature and the location of the fighting. Vance returns to work as a member of the Gibbs team. Gibbs and Vance interview at Quantico; Abby figures out a piece of the puzzle but not another one; Vance and Gibbs chat, as do Vance and Ziva. Gibbs and McGee find a dead private first-class with multiple wounds; Duck and Gibbs compare notes, then McGee finds details in medical records, and Ducky makes an astute observation. Gibbs and Vance confront the man responsible for the wounds and hear his explanation; then the two of them talk in the basement, and Gibbs helps Vance to understand family matters.