Having reached the age of twelve summers, Dal--a Cro-Magnon boy, looks forward to his manhood initiation. But his father informs him that Dal is being passed over because he isn't ready. Making matters worse, Dal's eleven-year-old friend Cog is accepted into the initiation. Ashamed, Dal flees the cave, falls in a raging river, and embarks upon an adventure that leads him into the Land of the North Caves, where he is injured in a fall. Rescued by a Neanderthal boy, Dal is taken to the boy's cave. Dal is distrusted because he is different, and is accused of stealing. He is then sent on a quest to battle a mighty cave lion to gain acceptance. Mar, the boy who rescued him, joins him on this futile quest. Dal knows that he can't clear his name without facing this awesome beast. And he can never return home without first clearing his name among the Neanderthals. Together, Dal and Mar encounter the wicked lion. Will they be successful in their quest, or be brutally savaged and eaten by the wicked beast? And what other problems do they uncover on their journey?