The wizard Sholow is hosting the Challenge of the Wizards. Several wizards will employ agents to seek out the legendary Helmet of Power. Sholow blackmails Thundarr (by threatening an innocent village) into acting as his agent. Thundarr must overcome the agents of Chomm, Bazam, and Scorpous, the other challengers, and return with the helm.
Thundarr succeeds after a series of battles, and hands the Helm to Sholow. Thus empowered, Sholow has no intention of honoring his bargain to release the villagers, and a fight ensues. In the end, Thundarr is saved by Ariel's quick thinking, when she discovers the Helm's sole weakness.