Despereaux Tilling is a tiny mouse graced with oversized ears who was born too big for his little world. The tale follows Despereaux on his adventures from Mouse World, where he is born, to the castle library, the princess's chambers, and even a rat-filled dungeon. With the love of Princess Pea and the friendship of a unique rat named Roscuro, Despereaux finds the courage of a knight in shining armor.

Tale of a mouse with big ears who finds himself loving to read rather than destroying books. So he's banished. In the dungeon he becomes friend with a rat, who is also a bit different from others of his kind. He meets a princess named Pea, falls for her, and then after she's kidnapped and taken to the dungeon, he rescues her, using what he learned in the books.