In a rented room outside Plymouth in 1685, a daughter is born as her half-brother is dying. Her mother makes a decision: Mary will become Mark, and Ma will continue to collect his inheritance money. Mary’s dual existence as Mark will lead to a role as a footman in a grand house, serving a French mistress; to the navy, learning who to trust and how to navigate by the stars; and to the army and the battlegrounds of Flanders, finding love among the bloodshed and the mud. But none of this will stop Mary yearning for the sea. Drawn back to the water, Mary must reinvent herself yet again, for a woman aboard a ship is a dangerous thing. This time Mary will become something more dangerous than a woman. She will become a pirate.