Hanna-Barbera animation about the famed whale and his pal Scooby the seal, who undertake undersea adventures. On land, a prehistoric boy becomes the invincible Mightor when troubles arise.
Grok steals the Golden Rok, which has the ability to control any animal. It falls out of his pouch as he is leaving and hits Little Rok on the head. While fighting a dinosaur, Little Rok discovers the power of the Golden Rok. As he is experimenting with it, Grok returns and steals it back. Tor hears animals fighting in the area that Little Rok had gone. He turns himself into Mightor and heads off to investigate.
Korg has been banished from the village by Chief Pondo. He wants to get even so he sends an army of animals to attack the village. Korg demands that Pondo step down and appoint him the new chief or he will bring his animals back and destroy the village. Tor, not wanting his friends to be harmed, turns into Mightor and battles with Korg to try and save the village.