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24 Episodes 1975 - 1976
Episode 1
Sun, Sep 21, 197560 mins
The pilot episode that introduces the main cast and sets the stage for the series. Located on the moon is Moonbase Alpha, a multinational scientific research facility. One of its duties is to also monitor and coordinate the activities surrounding two large lunar dumping sites where nuclear waste from Earth is disposed of. The Alphans are trying to launch a fast-tracked manned probe to an 'approaching' planet named Meta. The Meta Probe is in jeopardy since two of the mission crew have come down with a mysterious illness. The Alphans tie the illness to the nuclear waste about the time the smaller site unexpectedly explodes. While the Alphans try to avert a similar explosion in the larger waste site, it explodes also, and pushes the Moon out of the Earth's orbit, leaving the Alphans stranded on a moon destined to wander the universe.

Episode 2
60 mins
A wandering alien force arrived on Alpha and occupies the body of technician Anton Zoref. He begins absorbing energy heat from everything--and everyone--around him, putting the base at risk as the entity's thirst for heat becomes insatiable.

Episode 3
50 mins
After destroying an asteroid on a collision course with the moon, an even larger obstacle appears - an entire planet! On a recon mission, John Koenig encounters an inhabitant who convinces him- on the basis of faith- that the moon and the planet must collide. But no one else supports Koenig's stand.

Episode 4
60 mins
Moonbase Alpha is attacked and devastated by warships from a nearby planet. With half of its population dead Alpha can no longer survive. Commander Koenig and Dr. Russel go to the alien world to plead for the survivors, but the inhabitants wish no one to disturb their serene existence.

Episode 5
60 mins
Koenig, Russell and Bergman are stranded on the ice planet Ultima Thule, where Dr. Cabot Rowland leads a lost colony of scientists who were stranded there 800 years ago via a time warp, and have apparently gained immortality... but at what cost?

Episode 6
60 mins
A Voyager probe originally from Earth approaches the Moon. its Queller drive spewing highly-destructive radiation. The creator of the probe is on Alpha under an assumed name, and the ships of an alien race wiped out by the drive also approach seeking vengeance.

Episode 7
60 mins
A mother gives birth to Alpha's first child, and immediately rejects it. Meanwhile, the child, Jackie, grows to 5 years old in a matter of seconds. Koenig suspects Jackie is a spearhead of an alien invasion force. Alien spaceships arrive, seemingly confirm his suspicions.

Episode 8
60 mins
After surviving the first exploratory mission outside of the solar system. pilot Tony Cellini has the chance to redeem himself when the wandering Moon crosses the path of the same graveyard of ships where Cellini lost his first crew... to a life-sucking creature that doesn't show up on sensors.

Episode 9
60 mins
The Alphans pick up a distress signal from an alien mile-long generation ship ahead of them. The remaining residents ask Koenig for help, but they harbor a dark secret that puts the split-up rescue team that go on-board in danger of their lives.

Episode 10
60 mins
The moon is approaching a black hole. Professor Bergman is a able to rig up an energy shield around the moonbase, but Commander Koenig feels this is only a desperate measure and has an Eagle with six personnel dispatched as the rest of the moonbase await certain death.

Episode 11
60 mins
The Moon approaches planet Piri, and Computer says that the planet can sustain them. But they lose three advance men, and Koenig has his suspicions upon checking out the planet's surface even though everyone else is ecstatically convinced, even Helena and Victor.

Episode 12
50 mins
The Alphans retrieve an alien humanoid, Balor, from the asteroid where he's imprisoned. Balor is immortal and claims his own people imprisoned him, but he soon reveals that he's a sadist who thrives on the pain of others and only wants obedient worshipers.

Episode 13
60 mins
While returning from a reconnaissance mission to a nearby planet which appears to be capable of sustaining life, an Eagle team pass out and the ship is brought back under remote control. Upon arrival a passenger is found aboard the Eagle, who appears to be Dr. Helena Russell's husband, long presumed dead after a failed mission to Jupiter five years prior. The Moon Base Alpha crew must determine how this seemingly impossible situation occurred, all the while slowly drifting out of range of the planet which has offered the promise of a new home. Koenig must decide whether to go ahead with the evacuation to the planet before time runs out, but questions remain about the true nature of Dr. Russell's "late" husband, and whether the planet is truly safe.

Episode 14
Mon, Jan 19, 197660 mins
Five survivors of a doomed planet crash on the Moon, and appeal to the Alphans for help continuing on their voyager. Since they were heading to Earth in stasis, Commissioner Simmonds sees a way to get home... and will do anything to make sure he has the opportunity.

Episode 15
60 mins
The Alphans find an Earth-like planet shrouded in mist, and lose contact with a recon team and a rescue team sent to find them. A third team goes down, and discovers that the mist has reverted the first two teams back 40,000 years to become cavemen.

Episode 16
60 mins
An unknown space phenomenon seems to duplicate the moon (and everyone on it), then sends the doppelgänger into hyperspace. Everyone recovers except Regina Kesslann, who believes she's been living back "home" and is married to Alan Carter. In an astonishing coincidence, the Alphans discover the moon returning to Earth's solar system and Regina mysteriously dies when the moon re-enters the Earth's orbit. The Alphans are unable to contact anyone on Earth, which seems to have experienced an extinction event. Suddenly another moon appears in Earth's orbit which is discovered to be on a collision course with their own. A recon mission is assembled to find answers.

Episode 17
60 mins
As the Alphans are planning to explore the planet Ariel, a 'missile' attaches itself to the en route Eagle. Upon returning to Alpha, the 'missile' gives the Alphans a lunar atmosphere. But the joy at the possibility of making a new world out of the Moon is short lived, as the moon does not enter orbit around the planet or its sun, and Alpha faces destruction from the newly acquired lunar air.

Episode 18
60 mins
A visiting bizarrely-constructed alien ship sends out a friendly-sounding voice invites the team of Koenig, Helena, and Victor Bergman to enter the vessel. They have been communicating with the ship itself, which insists that the Alphans send out an Eagle full of materials it needs for survival. The sole "human" entity aboard the ship informs the Alphans that he constructed the ship, which calls itself Gwent, and had infused it with his own personality. After the man (called "Companion") dies, the Alphans realize the supplies aren't the only thing that the lonely Gwent has come for.

Episode 19
60 mins
Maintenance technician Ted Clifford is possessed by an eerie yellow glow, which ultimately kills him. It transpires that it is coming from a planet called Triton, which captures the Alphans and insists that Helena should become the Eyes of Triton. Before long she is acting just as Ted Clifford did before his death.

Episode 20
60 mins
After attempting to investigate a nearby planet, the reconnaissance Eagle goes haywire and crashes on the moon. Two of the crew were injured; Commander Koenig lay in a coma. Meanwhile, Koenig has been brought to the planet Zenno (which was not the planet they were investigating) to be studied by Raan, an alien anthropologist who considers mankind to be their "missing link". Koenig is informed that his body on Alpha will soon perish and he will spend the remainder of his life on Zenno as a "guest" to be subjected to one psychological experiment after another.

Episode 21
50 mins
Alien glyphs appear on all of Alpha's screens. Koenig sends an Eagle to investigate. The Eagle is lost and the pilot is taken over by a huge, alien 'Space Brain', using him as a channel to make the Alphans do its bidding. Koenig has to destroy it.

Episode 22
60 mins
Dan Mateo, one of Alpha's botanists, believes that he can increase their food supply by communicating telepathically with his plants. After passing out during one of his electronic experiments, Alpha seems to become haunted by a murderous and disfigured spirit.

Episode 23
60 mins
The Alphans land on the planet Arkadia, where glyphs suggest it is the cradle of civilisation from which life on Earth began. Now it is desolate and Koenig feels it is unsuitable for colonisation. Two renegade crew members have other ideas, however, and take Helena hostage in their demands to settle on Arkadia.

Episode 24
60 mins
The Alphans find themselves caught up in a long-running war between two rival planets, Betha and Delta. When a Bethan gunship, which has landed on the moon as a tactical advantage, appears to have been hit its commander Dione seeks sanctuary with the Alphans. Koenig attempts to negotiate a truce but Dione has other ideas...
