Billy and Sheena go with their Uncle, Dr. Deep, to search for treasure and are pursued by pirates who have been dead for two hundred years, and when Billy and Sheena return to land and visit Horrorland they encounter their worse fears.

Revenge of the living dummy: Britney Crosby thinks her cousin Ethan is pretty weird -- and she happens to be right. Ethan won't stop tormenting Britney with an old ventriloquist's dummy. And the puppet has plans for Britney, too! Creep from the deep: Billy and Sheena always expect adventure when they join their uncle, Dr. Deep, about his hi-tech boat. What they don't expect is a treasure hunt leading to a 200-year-old sea captain...who refuses to...