Cubs Stellan and Jytte survived their treacherous trek across the Nunquivik, but their quest to rescue their mother has only begun. Svenna is imprisoned at the sinister Ice Clockthe headquarters of the Grand Patekwhose dangerous influence is spreading throughout the bear kingdom. Only one bear has ever stood up to the Grand Patek: Svern, the cubs' father, a famous warrior who's been in exile for years. And so, along with their friend Third, the cubs set out to find Svern in the legendary Den of Forever Frosta place some bears claim never existed at all. But time is running out. The Grand Patek has a secret weapon at his disposalone with the power to destroy everything the creatures of Ga'Hoole hold dear.