Oneshrew was a tracker in the Guosim tribe of Log-a-Log Togey who had an extremely sharp temper. She was the sister of Twoshrew, Threeshrew, Fourshrew, Fiveshrew and Eightshrew. The reason for her odd name was that her father had many children, and he could not be bothered to give them real names.
She and Twoshrew were sent to meet Rakkety Tam MacBurl when he emerged from the crows' pine groves. She was also sent with Tam to lead the way to Redwall Abbey.