The film's main character is Carter Druse, a private who joined the union army in defiance of his Virginia heritage and family who live near where the fighting is about to commence. His father, though broken-hearted, tells Carter to follow his sense of duty and to not tell his dying mother. Because he grew up in the terrain, Druse is assigned as a sentinel on a high ridge overlooking a valley where his regiment is awaiting their surprise attack on the confederates. He falls asleep, but is awakened by an angelic force just in time to witness a mysterious, statuesque horseman who has identified the union regiments, but has not yet discovered Druse's position. Druse has his hand on his rifle ready to fire, they look into eachother's eyes before Druse, after hesitating, decides it is his duty to kill the confederate horseman spy to protect the union's position. One officer witnessed the falling horseman over the sheer cliff, appearing to fly, gives up his search for the body below, and decides not to report it to his superior. A sargeant who heard the shot interviews Druse, who confesses that the man he killed was his father.
