While three of the fiercest warriors in human history—a Viking raider, a ninja in feudal Japan, and a WWII pilot—are killers in their own right, they are merely prey for their new opponent: the ultimate killer of killers.

While three of the fiercest warriors in human history—a Viking raider, a ninja in feudal Japan, and a WWII pilot—are killers in their own right, they are merely prey for their new opponent: the ultimate killer of killers.