The Clue Club investigate the dock area where a sea monster dwells. What spooks them is someone named Doomsday who seems to be observing them. After combing the shorelines the Clue Club and Sheriff Bagley catch the three diamond smugglers who were able to conceal the diamonds in golf balls.
Elenco: Bob Hastings , Paul Winchell , John Stephenson , Tara Talboy , Jim MacGeorge , Patricia Stich , David Jolliffe .