The lost sword of Martin the Warrior is the only thing that can save Redwall Abbey from the evil, one-eyed rat Cluny and his greedy horde. The young, bumbling mouse Matthias (formerly Redwall's most awkward novice) vows to recover the legendary weapon. In the course of his quest, Matthias forges strong ties with various local animals of Mossflower Wood. As much as the magic of the sword, it is the help of these new friends that enables Matthias to defeat Cluny once and for all. It is this challenge to defeat Cluny the Scourge and his battle-seasoned characters that make Matthias become the unlikeliest of heroes.