Seekers #5: Fire in the Sky by Erin Hunter

The spirits dance like fire in the sky. . . .

The three cubs—Kallik, Toklo, and Lusa—along with their shape-shifting companion, Ujurak, stand on the edge of the sea-ice under the blazing Northern Lights. The land has come to an end, but the bears' journey is far from over. Now they must put their trust in Kallik's paws, as she feels the ice pulling her out toward the ocean.

Life on the ice is more difficult than the bears imagined. While Kallik struggles to remember her polar bear roots, Toklo bristles in the unfamiliar territory and Lusa gets weaker by the day; black and brown bears don't belong on the ice. Meanwhile, Ujurak learns firsthand what lurks beneath the whorls and bubbles of the ice, and what he discovers will change everything.

Just when it seems like they'll never survive in the frozen wilderness, a mystical encounter with a bear spirit assures them that all will be well. But this strange vision leads to even more questions, and ultimately it might tear the bears apart—this time for good—as the next steps of their journey come into focus.