The story chronicled the battle between the crew of the semi-transformable carrier Daikū Maryū (also called the Kargosaur in the US version, and also known as the Great Space Dragon) and the Super Robot Gaiking invented by Dr. Daimonji (Prof.
The leader of the alien villains was named Prince Darius or Dario el Grande in the Spanish version and all of their ships and mecha were fish-shaped, which most likely inspired the Darius series of video games.