The Hardy boys and their father solve a mystery involving inexplicable crashes of highspeed race cars being used to test an experimental turbine motor.
Kimmy encounters two wild children who have grown up in the hills of Australia and tries to protect them from the unknown person who murdered their father.
Sixteen-year-old Cristina is forced to evaluate her sophisticated world of elegant New York apartments, private schools, and rich friends when a girl she knows is murdered after a party they both attended.
After Spinner Shafter catches a cutthroat trout in the Snake River, she and her cousin Alligator search the nearby mountains to determine where the endangered fish came from and how it survived.