Crisp's Folly, hole 13 at Whiteoaks Golf Club, is unpredictable to say the least. As Alistair Kingslake, Jerry Drinkwater, Ed Monkberry and Miles Tully approach the hole, Kingslake raises the stakes with a £1000 bet. Discovering his ball is not on the fairway, Kingslake enters the woods to find it. When Drinkwater follows a few moments later, he discovers his body beaten to death. Barnaby and Jones investigate and uncover some sinister secrets at the well to-do club.