This film is based on the popular pulp novel series Perry Rhodan. The story begins with the spacecraft Stardust being launched from Earth to explore the moon in an attempt to discover new deposits of a new element, much more powerful than Uranium or any other source of energy ever discovered. The plot takes a split approach with the Stardust being taken over by a mysterious force, causing it to land on the Dark side of the Moon, and out of contact with Earth. Meanwhile on earth, an organized crime boss has planted an agent amongst the crew of the Stardust to attempt to take the energy source somehow, if it is found. Soon Perry Rhodan and his crew discover an alien starship which has had to make an emergency landing on the Moon due to technical problems. The ship is commanded by the Alien Crest and the beautiful captain Thora. They are informed that Crest, one of the last great scientists of their dying civilization is very ill.The Stardust's Doctor is asked to examine Crest and he does, and discovers Crest has Lukemia. There is hope however. The Doctor knows of a researcher on Earth who has developed a cure for Lukemia. The crew of the Stardust are brought along in a smaller but very capable emergency craft, to Earth, in an attempt to enlist the Researchers aid to cure crest. What they don't know however is that the spy has informed the crime lord about the mission, and a trap has been set to capture Crest and the Arkonide ship on the moon. There is a lot of true 60s style action as a General who discovered the pilot ship on earth, attempts to capture it to no avail. Afterwards Major Rhodan and his co-pilot seek out and recruit the fake researcher who promptly attempts to take over the Arkonite ship. The crime lord is defeated however, with the aid of the robots that the Arrkonites use to run the day to day operations of their ships, and the real researcher is rescued and cures Crest. The final segment has Major Perry Rhodan rescuing Thora, who had been temporarily captured by the crime lord. At the end, the very militant and strong willed Thora falls for Major Rhodan's charms and the two races (after curing Crest) look forward to a long and trusted partnership.