Handsome surfer Duke Williams rides a giant tsunami to the island. At first, the castaways are excited as Duke thinks he will turn around and surf back to Hawaii (and send help). However, after seeing Mary Ann and Ginger, he decides he may want to stay for a while. The castaways must come up with a plan to make him want to leave for Hawaii.
Elenco: Bob Denver , Alan Hale Jr. , Russell Johnson , Jim Backus , Natalie Schafer , Tina Louise , Dawn Wells .