The Pirates started the war, and now they must end it. Pirate captain Alethea Hera has abandoned her pursuit of treasure to hide her submarine, the Barracuda, below the Arctic ice. It's a hard life eating nothing but seal blubber and dried biscuits, but necessary to keep them safe. Her traitorous former quartermaster Kei is spreading a reign of terror throughout Undersea, and not even its most powerful leaders can stop her. Alethea's daughter Marina is just as melancholy. Hiding under the ice means she'll never see Thara, the beautiful shieldmaiden she's in love with, ever again. Little does she know that Thara is also thinking about her, whenever she's not trying to steal a legendary treasure hoard from Kei's submarine. But Kei has used devious means to find Alethea and kidnap members of her crew for her ever-expanding army. Now Alethea must travel to the farthest corners of Undersea - from mermaid palaces to lost worlds - and turn enemies into allies. Can Alethea save the world, if it means fighting her oldest friend?