After being run out of Boneville, the Bone cousins become separated and lost in a desert. Later, they arrive in a forested valley filled with wonderful and terrifying creatures.
Phoney Bone rigs the Spring Fair's annual Great Cow Race by putting Smiley in a bovine disguise and convincing everyone to bet their livestock on the Mystery Cow.
As the Bone cousins race to save the ancient city of Atheia from The Hooded One, they realize that time is short and hurry to accomplish their goal before the city is totally destroyed.
