Aboard the US Navy destroyer USS Manfred, the ensign locker is home to the five junior officers. Admiral Ensign is a Naval Academy graduate and career minded. Cowboy is a Navy cowboy. Almost, the senior ensign, is almost normal. Jon Zachery, Two Buckets, the junior officer, gets seasick. A North Vietnamese PT boat attack, missions to support the Marines in northern South Vietnam, threats from Viet Cong sappers in the Saigon River all present challenges to the denizens of the ensign locker. The influence of the anti-war movement is felt both on board Manfred and back home after the ship returns to the States.