Soul Eater — Michelle Paver

It's winter, and Wolf, Torak's beloved pack-brother, has been captured by an unknown foe. In a desperate bid to rescue him, Torak and Renn must brave the frozen wilderness of the Far North.

As they battle for survival amid howling blizzards and the ever-present menace of the great white bear, their friendship is tested to the breaking point, and Torak is forced to get closer to his enemies than ever before. . . .

Soul Eater is a haunting story of loyalty and loss, a chilling portrayal of the nature of evil, and the next step in the perilous journey that began with Wolf Brother and Spirit Walker.