In the howling, snowy north, a young common kestrel named Skarlath is lost in a snowstorm after leaving the nest, and is captured by the cruel ferret Swartt Sixclaw and his group of vermin.

As the young badger could not remember his name, Skarlath dubs him Sunflash after the distinctive golden stripe running down his snout.

Swartt takes over his large horde and marries his daughter, Bluefen, who gives birth to his son before dying.

By this time, Swartt Sixclaw and his large horde have passed through the Redwall region of Mossflower, which is efficiently defended by the resident squirrels and otters.

Abbess Meriam and Bella of Brocktree decide to entrust the baby to the care of Bryony, a young mousemaid, and Togget, her sensible mole friend.

As a youngster he is naughty and mischievous, but as a young adult his true vermin nature begins to show through, as the ferret would steal, lie, and be generally unpleasant to all, especially his adopted mother, Bryony.

Now allied to a smooth-talking ferret corsair named Zigu, an attack is mounted and war begins.

In the ensuing attack, Nightshade kills Skarlath with a poison arrow, only to be slain by Sunflash seconds later.

Bryony, unsure if Veil really meant to save her, accepted that the young ferret she always defended had always been evil.