The Overlords foresee an environmental emergency on Earth, so send Spectreman to investigate. Going undercover as George, he starts work with the Pollution Research and Control Squad in Tokyo. But Dr. Gori is also heading to Earth.
After shooting the android out of the sky, Gori sends Karras to recover it. The media reports that a flying man was seen attacking the monster and names him Spectreman. Gori discovers that Spectreman was sent by Nebulon71 to protect Earth.
The Dustman tells Spectreman he doesn't want go on living that way, and asks him to destroy him. When he refuses, he jumps into the sea and dissolves, leaving only his hand.
The team try to find Rita and Johnny in the collapsed building, whilst George must play the spirit chords to reactivate his receiver so that he can communicate with Overlord and transform into Spectreman.
Dr. Gori sends Karras down to Earth to find out what is the prime killer is there. He returns with a photo of a hit-and-run driver, who put a young boy in hospital.
With his right arm out of commission from his battle with King Satan, Spectreman's powers have been diminished; but he knows he must try and render Magulah harmless and moves in to battle the monster.
In a thick fog, a ship runs aground and is then attacked by a seaweed creature. Investigating the incident, the team find thousands of giant eggs on the beach.
Returning to the moon, the Apollo astronauts report the discovery of a strange iridescent purple stone, similar to radioactive samples found there previously, and return to Earth with it.
Dr. Gori believes Moonthunder destroyed Spectreman, so he calls out Vegaron from the Monsters' Graveyard. But Spectreman was recovered by Overlord and is on board a Nebula space station. Pollution Research and Control get new equipment.
Karras confirms that Spectreman is dead and goes to steal the Palanium from the laboratory. Spectreman asks the children to cut a tree branch which is blocking him communication with Overlord so that he be revived.
A gas-ejecting creature is seen in the hills. The G-men fly out, shoot it and leave. When a young, grass-whistling, boy is bullied by other children, the monster saves him and the boy removes a splinter from the creature's paw.
Schoolboy Gary tells his mother to stay out of his room, and the strange glow in his eye causes her to worry. Then a spaceship appears outside the house.
Young women in the city are being attacked and their blood drained, apparently by a vampire. George receives an unexpected visitor when working late at the office.
An experimental drug is injected into a dog's brain, to increase its intelligence. When he hears it succeeded, a moron volunteers to be a human guinea pig.
