Milo, a very bored little boy, receives an unusual package one day: a make–believe tollbooth. When he drives through it in his electric toy car, he is suddenly transported to the Land Beyond, a fantastic world of imagination. On his way to Dictionopolis, one of the country’s two capitals, he meets Tock, the watchdog who joins him on his journey. In Dictionopolis, Milo meets King Azaz who presides over the world of letters and words. Azaz sends Milo on a mission to rescue two princesses, Rhyme and Reason, who are imprisoned in the Castle in the Air, which floats hundreds of feet off the ground. Milo and Tock leave Dictionopolis with a new companion, the Humbug, whom Azaz has sent along as a guide. The three head toward Digitopolis where they hope to persuade the Mathemagician to release the princesses.