"Seinfeld" Is Unfunny: A kid from the modern world finds a doorway to another world and finds himself saving it. Sounds like almost every other escapist fantasy book out there, huh? Not so much in The '60s. Even in the face of books like The Chronicles of Narnia, the premise can come off as somewhat stale and antiquated.
Unintentional Period Piece: Norton Juster noted that, in the 21st century, tollbooths have fallen into disuse and aren't so common as they were in the time his novel was written.
Values Resonance: In the "appreciation by Maurice Sendak" that accompanies the Yearling edition of the book, Sendak notes how the monsters and obstacles in the book are "prophetic and scarily pertinent" to modern living and how Juster's "allegorical monsters have become all too real".
Before he properly drives through, Milo spends a couple minutes just screwing around with the tollbooth, watching how his live-action and cartoon selves interact with it for no other reason than to show off the special effects.
Chroma the Great conducts the sunset and Milo distracts him. Even though the colors are messed up, Milo, Tock, and the Humbug simply drive off.
Nightmare Fuel: The Doldrums are absolutely terrifying from one point of view. In a land in which thinking and breathing itself is outlawed, the very swamp comes alive to chase you, and if that's not bad enough, the personifications of Boredom, Sloth, and Lethargy will deliberately do their best to keep you where you are hiding their truly malign intentions under a relaxed and casual facade. A particularly sinister moment comes when the facade drops mid-song and the Lethargians start shooting devilishly triumphant looks at each other as their trap does its work on Milo.
Tear Jerker: Tok's Heroic Sacrifice against the combined Demon of Ignorance, with Milo not even allowed to properly mourn his potential death in order to rescue the Princesses. Especially, so as Tok was his first friend in the world and helped him out of his bored way of life.
The initial intro song of Milo, which details how uninterested Milo is concerning life in general, having a mellow and melancholy tone.
Milo having to leave the world of the Tollbooth with a greater appreciation for knowledge as the Tollbooth goes to another child's home so they can have their own journey. While he did save that world, the inability to see his friends again is very saddening.
Visual Effects of Awesome: Chuck Jones of Looney Tunes fame, brings the world of the Phantom Tollbooth to life with his usual elegant yet comedic designs, but also experiments with a variety of styles for the various characters to create designs for characters that drastically differ from his usual expertise, ranging from the heavily scratchy designs for the Demons of Ignorance, the marker look of the Awful Dyne, and the liquidy Lethargians.
The background images are also intricate and beautiful to look at, combining elements of alphabets, numbers, etc.
