Kensho arrives at the Crystal Castle where he once was an acolyte and has been asked to become Thra's leader. However, he feels that before accepting the position, he must face the mistakes of the past. Meanwhile, the realm of Mithra that is below Thra is being reconstructed by the newly crowned EmberQueen Thurma, whose rule is challenged when evidence is discovered that another Fireling has a competing claim to the throne.