Woodruff's book is a treasure hunt for a destination, with hints rattling like hail all around readers. Gramps is taking Jack out for the day, but he's not letting on just where they are headed. He does give Jack clues--impossible clues--e.g., there will be monkeys there, and perhaps they can bring some home. Sea turtles, pastries, mountains, dragons, and knights also come up in conversation. Throughout the journey, Fisher drops additional hints in color-mad, busy illustrations that feature a lot of books. When the two finally pull up in front of the library, it comes not as a surprise but as a pleasant inevitability.