The Steel Shark was a deep-sea raider and pirate responsible for sinking and plundering ships near the island of Monango as well as kidnapping Jane Wells, the daughter of the governor of Monongo. The Steel Shark's pirating and kidnapping get the attention of Naval officials who send Lt. Dick Jones to rescue the captive girl and bring the undersea pirate to justice. In the first issue of Rocket Comics, he was bald and green skinned but, in subsequent appearances, looked like a more normal submarine commander.