The four bears finally arrive at the legendary Last Great Wilderness, thinking it is the end of their long journey, but they discover that their true mission has really just begun.

At the edge of the Endless Ice, the four bears Ujurak, Toklo, Lusa, and Kallik reach Star Island, where a large group of bears is in trouble but believes Lusa is destined to help bring back the favor of the spirits.

Despite their misgivings about the many dangers that lie ahead, the bears venture out onto the Everlasting Ice and learn of their final destination with the help of a mystical bear spirit.

"Toklo, Kallik, Lusa, and Yakone trek onward toward the Melting Sea, the site of Kallik's traumatic cubhood--and prepare to be separated for the first time since their journey began"--

While researching the existence of dragons for an essay that could win him a trip to the Arctic, Chris opens himself to the possibility that a great, ancient treasure exists there, guarded by bears, and that he has some role in its protection.