Matthias is a young mouse who lives at Redwall, an establishment comparable to a medieval monastery in the English countryside. Inside the monastery, “Matthias cut a comical little figure as he wobbled his way along the cloisters, with his large sandals flip-flopping and his tail peeping from beneath the baggy folds of an oversized novice’s habit” (13).

The elderly Abbot Mortimer is fond of the young mouse, who was once an orphan left at Redwall’s door. Matthias tells Father Abbot that he dreams of someday being a great hero like Martin the Warrior, who once saved all the woodland creatures from barbarian hordes. Father Abbot explains that after his triumph in battle, Martin devoted his life to peace and founded the Redwall order to look after all the inhabitants of Mossflower. Father Abbot tries to distract Matthias from dreams of glory by sending him to catch a fish for a special celebration dinner.

While everyone at Redwall prepares for the festivities, they have no idea that trouble is headed their way in the form of Cluny the Scourge: “He was big, and tough; an evil rat with ragged fur and curved, jagged teeth. He wore a black eyepatch; his eye had been torn out in battle with a pike” (17).