"Ghosts of Space" is the thirty-sixth episode of the first season of Fireball XL5. It originally aired on ATV in the United Kingdom on October 6, 1963.
The episode opens on a far-flung planet, in what appears to be a ghost town. Soon, Fireball XL5 nears the planet, soon revealed to be called Electon, detaches Fireball Jr, with Steve Zodiac and a man named Fraser on board. Steve explains that the people of Electon are peaceful folk who lived in towns scattered all over the planet. Fireball Jr soon lands on the surface of Electon, and Steve tells Fraser that the town they are heading to is on the other side of the hills. Apparently, Fraser is the one heading to the town instead of the XL5 crew. Once Fraser leaves, Fireball Jr heads back to XL5.
Meanwhile, Fraser arrives at his destination and finds the town empty. He enters one of the buildings and determines that no one has used it in weeks, and someone has left their meal unfinished and draped in cobwebs. Fraser thinks that something must have scared off the inhabitants, and suddenly, the door closes on him. Fraser thinks it's just the wind and prepares to move on, making the decision to stay at a hotel on the edge of town, at Steve's suggestion. And just like the building from earlier, the hotel is deserted, but the people did leave behind a good stock of food. While Fraser goes upstairs to check the bedrooms, the cabinet door where the food is kept closes all by itself.
While the crew on Fireball XL5 think the people of Electon are giving Fraser a welcome party in his honor, turns out that Fraser has made a discovery, for he has found a rock that glows, an electric rock. Fraser then decides to have a meal and head for bed, thinking he might find some more electric rocks in the morning. Soon, Fraser is asleep, and the next morning, finds more electric rocks. Thinking that they might be worth a fortune on Earth, he decides to take some samples. And within a month, Fraser has a whole pile of electric rocks. However, he soon finds himself greed-stricken, only looking to share some electric rock with Steve, but no one else.
Soon, Fraser puts his shovel in the ground, but a small explosion ensues. Fraser realizes that he found some exploding rock, and decides to use it to help him mine the electric ore. Meanwhile, on a not too distant planet near Electon called Groverous, two men prepare to go there in order to get some of the electric rock, revealing that they're the ones who scared off the inhabitants, due to their shy nature prohibiting them from talking to the people of Electon. The two Groverians use magnets on the front of their space craft to pull themselves toward Electon, and prepare to harvest the electric rock so the people of Groverous can light their homes. However, when they land, the hear an explosion, courtesy of Fraser and his explosive rocks. They soon spot Fraser, and decide to scare him away, while Fraser ends up getting worried that Fireball XL5 might not show up on time, after him being stranded for 80 days (or 3 months) on Electon.
Meanwhile, Fireball XL5 arrives over Electon, and the entire crew, save for the robot, heads to the surface in Fireball Jr. The Fireball crew meets Fraser, and the Groverians prepare to scare them as well as Fraser. Fraser asks the crew to help him load the rocks, but they refuse, since they know that they'd never get off the ground. But Fraser refuses to leave without them, though Steve says he'll take a sample, but Fraser gives him until morning to think it over. That night, Venus deuces that Fraser is suffering from a case of Space Melancholia.
Soon, Zoonie gets worried, but Steve tells him that nobody's in that ghost town but them, save for the Gorverians, who soon put their haunting plan to action. They start by making Zoonie's basket bed move on its own, then Venus's bed covers float, then a strange noise is heard, then a vase lifts off the ground, giving Venus a real fright. She goes to Steve and explains what happened, thinking that the hotel they're staying in is haunted. However, Steve doesn't believe her. Meanwhile, the professor's glasses start floating around, and tells Steve what happened, but he doesn't believe him either. Meanwhile, Venus hears what sounds like someone prowling around, but looks outside her room and spots the door closing by itself, but knows that Steve won't believe her.
At daybreak, the crew finds that Fraser is missing. Once they get dressed, they find Fraser has gone mad, saying they won't leave until his electric rocks are loaded aboard Fireball Jr and fires exploding rocks at the crew. Steve fakes his death, and gives the crew a plan, they try to talk some sense into him while he sneaks up on him from behind. However, the plan fails, and Fraser tells Steve, who has his ray gun out, if he fires his body will fall on the explosive rock and they'll all die. Steve drop his weapon, but Fraser decides to kill him anyway, but at the last moment, the Gorverians save the day. They thank Steve and explain why they're there, their timidity, and that they're the ones who scared the Electonites.
Afterwards, Steve and Venus head to Fireball Jr, and then to Fireball XL5, and head for home.