In the Mountains of Ignorance, the journeyers contend with demons like the Terrible Trivium and the Gelatinous Giant. After overcoming obstacles and their own fears, they reach the Castle in the Air. Princesses Rhyme and Reason welcome Milo and agree to return to Wisdom. Unable to enter the castle, the demons cut it loose, letting it drift away, but Milo realizes Tock can carry them down because 'time flies'. The demons pursue, but the armies of Wisdom repel them. Rhyme and Reason heal the divisions in the old Kingdom of Wisdom, Azaz and the Mathemagician are reconciled, and all enjoy a three-day celebration.