In the 1950's the Blackhawks encountered a costumed villain named Killer Shark. He was a pirate, looting the city of Kamard. Using a variety of submersible vehicles, Killer Shark often matched wits with the international flyers who destroyed his undersea base and each of his attack craft. Killer Shark joined with former Nazi SS Colonel Von Gross to form the Empire of Death. Its agents wore skull masks, possessed a fleet of aircraft, and operated from a giant solar powered flying skull. With agents around the world, the empire engaged in espionage and contract assassination with an eye towards world domination, until the Blackhawks slew Von Gross and closed the networks down. Killer Shark recently returned to battle Lady Blackhawk.