Do you dare join the Very Nearly Honorable League of Pirates?

Hilary Westfield has always dreamed of being a pirate. She enjoys defying authority, and she already owns a rather pointy sword. There's only one problem: The Very Nearly Honorable League of Pirates refuses to let any girl join their ranks of scourges and scallywags.

Girls belong at Miss Pimm's Finishing School for Delicate Ladies, learning to waltz, faint, and curtsy. But Hilary and her dearest friend, the gargoyle, have no use for such frivolous lessons—they are pirates! (Or very nearly.)

To escape from a life of petticoats and politeness, Hilary answers an advertisement for a pirate crew and suddenly finds herself swept up in a seafaring adventure that may or may not involve a map without an X, a magical treasure that likely doesn't exist, a rogue governess who insists on propriety, a crew of misfit scallywags, and the most treacherous—and unexpected—villain on the High Seas.

Will Hilary find the treasure in time? Will she become a true pirate after all? And what will become of the gargoyle?