Stephen Brownstone

Stephen Brownstone A.K.A. "Seasuit Stephen" was a marine biologist, shark hunter, and former ace. Stephen worked within the team to handle maritime criminal activities such as smuggling, ship hijacking, and other dockside affairs. He also took part in search and rescue operations concerning shipwrecks and people lost at sea. 
After Steve retired from the A.C.E.S. he operated as a Marine Biologist, studying sea life off the shores of Umburgh's waterfront. Steve seemingly ran into financial trouble because he was desperate to make money. Stephen eventually hired himself out to the local docks to find a solution to the infestation of sharks near the Waterfront. Stephen concluded that chemical runoff from nearby factories had killed off their natural food supply and adversely affected the shark's diet and behavior which caused them to be more aggressive and develop a taste for human flesh. 
Stephen then reluctantly made it his mission to kill the sharks within the bay in hopes that it would prevent any more deaths of dockworkers. Stephen mentions in his journal that he knows of the criminal activity happening at the docks but that in his old age he has become cowardly and desperate. Stephen began to use a shark cage to go beneath the harbor to eliminate the rest of the sharks. 
At some point, Stephen was killed, and his corpse can be found in a shark cage beneath the water. It is unclear how he died, but the bite marks on his corpse may suggest he was bitten by the sharks and bled to death.