Exploring new lands, adventures on the high seas, and finding great fortune are all things Rose Sweetsail dreams of. The trouble is, no one takes her seriously. As a part of the Sweetsail family, all she's ever been allowed to do is make sails for the lucky ships that get to sail away. Her sweet look and gentle voice do her no favors either. But the unicorn's true talent lies in ship architecture, and it is this that catches the attention of the dashing Captain Swashbuck. They strike a deal. Rose designs a ship that can do what no other has done before--sail to the legendary land of Equestria. In exchange, Swashbuck allows her to sail with him as his boatswain.

Of course, that isn't how things go. Who wants to read a story where everything goes according to plan, after all? No, no... This is an adventure of swashbuckling danger in an epic quest of revenge. It's also the fantastic tale of how one sweet pony comes to be the most feared pirate on the high seas.