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.

"The four bears are determined to reach Great Bear Lake before the longest day gathering, but when Lusa is separated from the others, she faces difficult questions about her future"--

As the four bears head toward warmer territories, polar bears Kallik and Yakone wonder if they've made a mistake leaving their natural home, while Toklo, desperate to leave the struggles of their journey behind, thinks about leaving the group and starting a new life on his own.

Three young bears of different species--one black, one polar, and one grizzly--travel on a perilous quest to the Northern Lights, escorting a shape-shifting grizzly cub whose destiny will affect them all.