For two years, twelve-year-old Tommy Klopt, his dad, Hoody, and his two brothers, Connor and Dillon, sailed the seas as Robin Hood-type pirates. After meeting, and almost getting killed, by a pirate from the 1600s turned evil ghost, Francois l'Olonnais, the family decides to head back to land and start over.
Life on land turns out badly for the family, and they set sail once again. It isn't long before l'Olonnais returns and brings a fellow ghost pirate, Captain Jacques Mignard with him. Mignard needs a mortal's help to retrieve his girlfriend, Cosette, and he heard Tommy can get the job done. Besides a time crunch, the biggest obstacle is a spiteful and tricky sea witch, Volange.