The evil Garoga aliens plan to take over Earth with their army of giant Fearbeasts. They are opposed by the members of a family from a planet called Peaceland that was also destroyed by Garoga. They use a variety of exotic vehicles and weapons but their primary weapon against Garoga is the oldest child Hikaru, who is able to transform into the giant Zone Fighter. Zone Fighter is sometimes aided in his battles by Godzilla (who at the time was portrayed as a heroic kaiju).