Soren and the pack are back! After Corin mined the coal, the Great Tree of Ga'Hoole entered a golden age. The young king is obsessed with the idea that the blood of the hagsmar flows in his veins, and his faithful friends decide to go on a journey to distract him from his painful thoughts. Meanwhile, a mysterious coal begins to have a strange effect on those remaining on the island and the Great Tree itself. It begins to change, and with it the souls of its defenders change. Someone needs to tell Corin and the pack what's happening on the island!