Mice of the Round Table, book 2: Voyage to AvalonJulie Leung2017

Young mouse Calib Christopher is just two tests away from becoming a squire to the Knights of Camelot. But all tests and training are forgotten when a young squirrel-maiden arrives at the castle with news of a mysterious plague. Soon all of Camelot is showing signs of the illness, animals and humans alike. Desperate to find a cure before the defenseless castle is attacked again by the Saxons, Calib and his friend Cecily set off on a voyage to find the mythical, healing land of Avalon.
But even as their journey takes them over land and sea, back at home, Calib's human friend Galahad discovers that the true enemy may have already found a way inside the castle walls.
Now it will take all of Calib's and Cecily's strength, courage, and wisdom - along with the help of surprising new friends and long-lost magic - to solve the mystery of the plague and make it back to Camelot before it's too late.

Titre original : Voyage to Avalon (2017)