When a sick oak tree threatens to fall and destroy the fairy village, Thalia and friends fly off to ask Rootmaster, a forest wizard, for help. Though mistrusting these "walkabouters" at first, Rootmaster agrees to help them. Meanwhile, Phaedon tries to poison Rootmaster with the same tree-killing elixir he used on the fairy oak tree. Thalia and friends, however, make it back just in time to prevent him from his evil doings.