While visiting their friend Wallis and her adopted daughter on Mount Desert Island, Maine, Josh, Dink, and Ruth Rose investigate why three white wolf cubs were stolen, and by whom.
When the umpire at the baseball game fundraiser is accused of stealing a collection of autographed baseballs, Dink, Josh, and Ruth Rose try to prove his innocence.
Dink, Josh, and Ruth Rose investigate the theft of a great deal of money from the belly of a nearly life-size Tyrannosaurus Rex model that their friend, Jud Wheat, is using to raise money for a dinosaur museum.
Dink, Josh, and Ruth Rose investigate the disappearance of a valuable racehorse that Dink's uncle and his friend, Forest Evans, have just bought and entered in a race at Saratoga.