The main plot follows the adventures of a mouse named Despereaux Tilling, as he sets out on his quest to rescue a beautiful human princess from the rats.

The book won the 2004 Newbery Medal award and has been adapted into a film, a video game, and a stage musical.

[1] In 2012 it was ranked number 51 among all-time children's novels in a survey published by School Library Journal—the second of three books by DiCamillo in the Top 100.

Despereaux, unlike other mice, spends much time reading, and particularly enjoys a book about a knight saving a princess and living happily ever after.

After he took a red table cloth from a prisoner who confessed that he traded his own daughter for it and didn't look back at her when he left her, Roscuro decided to go into the light; against the wishes of his friend, Botticelli Remorso.

Many years before Despereaux and Roscuro were born, a six-year-old girl named Miggery "Mig" Sow witnesses the death of her ill mother.

Mig's main job is to go down to the dungeons to deliver Gregory the jailer his meal and, while there, she meets Roscuro and confesses to him that her greatest wish is to become a princess.

Despereaux escapes the dungeons on a tray of Gregory's that Mig brings back to the kitchen, where he hears her conversation with Roscuro.

When Despereaux is attempting to flee, Mig chops off his tail with a knife so that she can tell Cook that she got a part of the "meecy".

Hovis gives him an entire spool of red thread and a sewing needle to serve as a sword for his quest to the dungeons.

On his way, he runs into Cook, who has grown so anxious from Pea's disappearance she has resorted to breaking the law and making soup.

The spool of thread rolls to Botticelli Remorso, who smells soup, tears, flour, oil, and the blood of a mouse.

Roscuro, catching a whiff of the soup left on Despereaux's whiskers, realizes he does not truly want to hurt anyone and begins crying.

[3] On December 2, 2008, a video game for the Nintendo DS, Wii, and PlayStation 2 of the same name based on the film was released.