The Sea Hawk is set over the years 1588–1593 and concerns a retired Cornish seafaring gentleman, Sir Oliver Tressilian, who is villainously betrayed by a jealous half-brother. After being forced to serve as a slave on a galley, Sir Oliver is liberated by Barbary pirates. He joins the pirates, gaining the name "Sakr-el-Bahr" (the hawk of the sea), and swears vengeance against his brother.