After his escape from the sentient prison, Incarceron, Finn finds that the Realm is not at all what he expected, and he does not know whether he is to be its king, how to free his imprisoned friends, or how to stop Incarceron's quest to be free of its own nature.

Their quest to find a secret relic with great power leads Master Galen and his sixteen-year-old apprentice Raffi into the Pit of Maar and the deep evil world at the heart of the Watch.