Finally Milo and Tock arrive in Dictionopolis. It is one of two capital cities of Wisdom. In Dictionopolis, Milo learns, all the world's letters are grown in orchards. The letters are sold in a vast marketplace. In this marketplace, Milo and Tock meet the spelling bee. He could spell anything. As they are talking, a beetle like creature called Humbug interrupts. He wanted to be introduced to Milo and Tock. The Spelling Bee get into a fight, where Milo is blamed and sent to prison for six million years.
In the prison, Milo meets a person called "Faintly Macabre, the not-so-wicked Which, who tells him the history of Wisdom's two rulers, King Azaz and the Mathemagician, and their adopted sisters, Rhyme and Reason. According to this story, the two princesses were unable to settle the long-standing argument between their brothers over whether letters or numbers are more important. Because they couldn't get the Kings to decide, they were sent to the Castle in the Air. The Castle in the Air was high in Mountains of Ignorance where the demons also lived. Milo states that if he ever gets out of jail, he will set the Which free by bringing back Rhyme and Reason. The policeman didn't care for keeping in jail, he just liked putting them there, so all Milo and Tock had to do to get out was press a button and they were free.
As soon as they stepped into the sunlight, one of the kings advisers escorted them to a banquet with the cabinet members, where he meets King Azaz the Unabridged. King Azaz agrees to allow the princesses to be rescued, providing his brother also agrees. However, Milo learns, that this is very unlikely, as the brothers have not agreed on anything for years. Milo and Tock then leave Dictionopolis with the blustering Humbug, whom Azaz has sent along as a guide, towards the Mathemagician's capital of Digitopolis.
The first place that they encountered after Dictionopolis was the Forest of Sight. There they meet Alec Bings, a little boy who sees through things. They walked awhile and soon found themselves in the twin cities of Reality and Illusions. There is hardly anything in these cities because the citizens never paid attention to the things so eventually they disappeared. In the city of illusions they watch Chroma and his orchestra of color conduct the sunset. Chroma does this everyday for sunrise and sunset. The next place that they go through is the Valley of Sound, where they encounter Dr. Kakafonous A. Dischord, who dispenses unpleasant noises. The next place is completely silent and is called the valley proper. Here, Milo visits the fortress of the Soundkeeper, creator of all sounds, who has withheld the valley's sounds because the inhabitants had stopped appreciating them. As directed by the valley's inhabitants, Milo secretly takes a sound from the Soundkeeper's fortress, which the people of the valley use to break open the palace's sound vault. Milo and his friends then continue their journey, taking a short detour to the Island of Conclusions.