While on an innocent field trip to Boston's historic Freedom Trail, ElsBeth Amelia Thistle, the littlest witch on Cape Cod, becomes entangled in a fateful kidnapping - and the action soon moves to the treacherous waters of Massachusetts Bay and finally to the old whaling port of Nantucket. With the help of a pirate captain ghost and several magical animal friends, ElsBeth and her classmates attempt to rescue a young Arabian prince in this daring sea adventure. And along the way they discover the most important lesson of all - the true meaning of the Legend of the Pirate.