Most good stories start with a fundamental list of ingredients: the initial situation, conflict, complication, climax, suspense, denouement, and conclusion. Great writers sometimes shake up the recipe and add some spice.
Exposition (Initial Situation)
The book opens up by introducing readers to a tiny mouse named Despereaux, who doesn't act like all his mice relatives and neighbors. He lives in a castle that belongs to King Phillip. One day Despereaux follows the sound of music into the the king's daughter's room, despite the fact that he's supposed to hide from all humans. He falls deeply in love with the Princess. Due to the enormity of Despereaux's transgression, the Mouse Council banishes him to the dungeons, where he'll surely be eaten by rats.
Rising Action (Conflict, Complication
Despereaux isn't the only creature in peril. There's a rat in the dungeons named Roscuro who holds quite the grudge against Princess Pea, Despereaux's beloved. He fell into the queen's soup and accidentally killed her after Princess Pea shrieked about a rat being in the castle. Roscuro has never been able to forgive the princess for looking at him with such disgust. And so he plots his revenge.
Climax (Crisis, Turning Point)
Despereaux escapes the dungeons with the help of the jailer, but the day finally comes when Roscuro can set his evil plan in motion. He convinces a servant named Mig to kidnap the princess at knife point, promising her that she and the princess will switch places and positions in life. Mig, abandoned by her father and mistreated her whole life, goes along with the plan. Of course, he has no intention of honoring this promise—he is a rat, after all. He keeps the princess in the dungeons and Despereaux has to rush in to save the day…even though he's just a tiny little mouse.
Falling Action
The next morning, the castle is in a tizzy because Princess Pea's gone missing. Roscuro keeps the princess in the dungeons and prepares to torture her, but Mig realizes that he's lied to her this whole time and decides that she isn't going to put up with his awful plan. And so with her help, Despereaux is able to stand up to Roscuro and save the princess. He brings her back to the castle where the king is overjoyed to see his daughter is safe and sound.
Resolution (Dénouement)
In the end, Despereaux and Princess Pea live happily ever after, and he's even allowed to hang out with her in the castle. She forgives Roscuro and lets him wander around the castle, too, although he's never the same afterwards. Even Mig, the servant girl, has her own happy ending. She discovers that her father is a prisoner in the dungeons, and after the princess sets him free, he takes care of Mig and treats her like a princess for the rest of her life. Last but not least, soup—which has been outlawed since the queen's death—is allowed in the kingdom again.