After her parents and brother are killed by Loyalists, fourteen-year-old Hannah leaves their farm and eventually, disguised as a boy, joins a pirate ship that preys on other ships to get supplies for the American Revolution.
Still disguised as a boy, now-seventeen-year-old Hannah Pritchard and her crew aboard the ship Hannah carry out missions for the Continental navy while searching for lost pirate treasure and trying to evade an evil pirate captain.