Once upon a time in the far away kingdom of Dor lived a brave and virtuous mouse with comically oversized ears who dreamt of becoming a knight. Banished from his home for having such lofty ambitions, Despereaux sets off on an amazing adventure with his good-hearted rat friend Roscuro. The two go on a very noble quest to rescue an endangered princess and save an entire kingdom from darkness.

Robbed of his birthright, Arthur comes up the hard way in the back alleys of the city. Once he pulls the sword from the stone, he is forced to acknowledge his true legacy, whether he likes it or not.