Brian Hawke, an officer aboard the British merchant ship The Monsoon, volunteers for a dangerous mission to infiltrate the pirate's base at Diego-Suarez on the coast of Madagascar. He is to pose as a deserter, and to make his disguise more convincing, he is given twenty lashes. Once he has arrived at Diego-Suarez he is greeted with an air of suspicion by the pirates, especially Captain Roc Brasiliano. Brasiliano orders him to appear before a tribunal of the Coast Captains to decide his fate. If they do not like him, he will be executed. Meanwhile, Hawke has caught the eye of Spitfire Stevens - the only woman amongst the Coast Captains - who inherited her position from her father.