The fourth adventure in the enchanted Mirrorworld leads to the Far East, where Jacob and Fox finally track down Will, who is travelling with a one of Jacob's worst enemies. Putting his feelings aside, Jacob agrees to travel with them to the beautiful Island of the Foxes in quest of another magical Mirror.

But their search quickly brings more peril in this land of dark forests, lush palaces and shapeshifters. As Jacob seeks security for himself and Fox, he is haunted by a disturbing pledge he once made that now threatens everything.