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A mystery illness strikes the moon. An eerie cloud utters a sentence of death. And a frightening space creature runs amok.[1]


A strange cloud appears over Alpha. It begins to interfere with the sensors, and to incapacitate the bulk of the crew, by making them weak and listless.

Act One[]

Eagle 6 is sent to investigate but fails to return after 4 days. Long after its fuel stores should have been exhausted Eagle 6 returns to Alpha. Pilot Tom Graham does not respond to Alpha's hails. Sensors detect no life, but the Eagle lands safely. When Tony and the few remaining security guards board, they find a large creature aboard. It attacks and they try to stop it with their stun guns. They fail. Outmatched by the creature, they retreat to Command Centre. Tony posts the few remaining security guards to watch the travel tube for signs of the beast. As Maya tries to get the relative position of the strange cloud, it speaks. Tony asks who they are and it replies that it's beyond their comprehension. It tells them that it has sent for Alpha's life support core. It returns the screens so they can observe the creature leaving the Travel Tube. Security fires rocket guns at the creature but it shrugs it off and proceeds to beat up the two man team. Tony sends Maya and Sandra to Medical Centre, and has the the computer lock all the doors on Alpha so they will only open and close at his voice command. He sends Bill Fraser to guard the corridor to Life Support, and tries to lure the creature into a vacuum chamber in Tech Lab 5.

Act Two[]

Maya wants to help him, but waits, per his wishes. Tony gets the creature to chase him into the vacuum chamber, confuses it, gets out, and locks it in. He depressurizes the chamber and lets Alan know what the situation is, as Koenig is still sedated. When he opens the door to make sure it's dead, the creature springs out and attacks. Tony manages to get away and down the hall before it catches up to him. Alan tells Maya to help Tony. She turns into a mouse and leaves Medical Center via an air vent. She arrives and tries to turn into the creature to even things even things up, but can't. She opts for another and attacks. She distracts the creature long enough to release Tony. When she can't get away from the creature, Tony releases high pressure carbon-dioxide which knocks the creature off its feet so they can get away. They go to Medical Center where Helena suggests a heavy duty tranquilizer to use against the creature. Tony uses the commposts to confuse the Creature and keep it from reaching Life Support before they do. They realize they can lead it by taunting it from the screens on the commposts. Maya has Tony lead it towards the Hydroponics Experimental Section that they can fill with chlorine. Alan calls Tony to find out what the alarm is about, and comes up with a plan to safeguard the Life Support systems. He calls Fraser and has Sandra explain how to build an electrical barrier across the hallway. Tony joins Maya in hydroponics. She has it all set up. They only need to get the creature to walk into the trap. Maya turns into an animal from the planet Kreno that is capable of breathing in a chlorine atmosphere. Tony calls to the creature and hides then Maya leads it into the room.

Act Three[]

The chlorine has no effect so Maya tries the tranquilizer gun. It also has no effect. The creature throws Maya into the door controls shorting them out. Tony has to break the window to give her an exit. They get away, but Maya is beginning to believe there is no stopping this creature. Tony, unwilling to give up, comes up with an idea to try to attack the cloud to see if they can affect its control over the beast. They go to the weapons section and fire the laser cannon into the cloud. The cloud thins and they see a diamond shape within. They target the object and it splits in two. As they monitor the creature it is disoriented. They think they have succeeded until the two halves rejoin. The voice from the cloud taunts them. They fire and split it again, then split both halves. All four pieces rejoin to the great amusement of the cloud. Realizing that this, too, was futile, they join Bill Fraser, who has completed his work on the electrical barrier, and wait for the creature to arrive. When it does, it tests the barrier and is repelled. But it gets up and tries again. The barrier weakens with its second attempt.

Act Four[]

When they realize that the creature has survived, they know that it will break through shortly. Tony confesses his love for Maya. Their kiss is interrupted when Fraser alerts them to the fact that the barrier won't hold. Fraser fires the rocket gun in a last ditch effort, but the creature shrugs it off and breaks through the barrier anyway. As it moves into Life Support, Maya realizes that the reason nothing worked against the creature, was that it was, in fact, a robot. It manages to remove the life support core, but Tony and Bill fight the robot, to try to retrieve it. Maya turns into a bee and enters its "ear" to land among the inner workings. She shorts out its circuitry, finally stopping it. Meanwhile the cloud has been diminishing in size until it vanishes.


Maya visits Tony in Medical Center with an armload of gifts. He asks if she recalls "the wild garbage" he told her when the creature was at Life Support. She promptly takes the gifts and leaves. He laughs knowing she is crazy about him.[2]


  • Int. Command Centre
  • Int. Medical Centre
  • Int. Weapons Section
  • Int. Life Support Centre
  • Int. Techlab 5
  • Int. Corridor by Hyrdoponics
  • Int. Alpha Corridor & Electrical Unit
  • Int. Alpha Corridor
  • Int. Travel Tube
  • Int. Eagle Pilot Section
  • Int. Eagle Passenger Section


International Titles

Country Title (Translation)
France/Canada Le nuage qui tue The Cloud Which Kills
Spain La nube Beta The Beta cloud
Germany Die Feuerwolke The Fire Cloud
Italy La Nuvola The Cloud
Japan Save the Life-supporting System!
Poland Oblok Beta
Portugal A Nuvem Beta The Beta Cloud
South Africa Die Beta-Wolk The Beta Cloud

Shooting script dated 11th June 1976. Filmed 20th July- 6th August 1976. Additional sequences scripted 1st Sept 1976, final shooting script 16th Sept, filmed 21st Sept-22nd Sept 1976 A "Double Up Helena" script, filmed while Landau and Bain were on holiday in the South of France.

In Starlog 40 (November 1980) Freiberger described the script: "What I did was try to get into the situation. How do you defeat the undefeatable? What intrigued me is that the Alphans could not seem to defeat this creature. Finally Maya becomes a bee and enters the creatures ear, discovering it to be a machine"

Bob Lynn met Dave Prowse at the Harrods department store when he asked for advice on exercise equipment. Immediately after the role in this episode he was cast as Darth Vader in Star Wars.


The cloud was made by injecting condensed milk into a water tank and filming from underneath. The milk was swirled to simulate laser hits. The nebula that first appears is the remnants of the supernova in Into Infinity. It is also seen in the Year 2 opening titles and in The Metamorph. Thanks to Marcus Lindroos.


  1. The Creature's molecular structure eludes Maya. How does she normally find something's molecular structure?
  2. How does a formless cloud construct a mechanical robot?
  3. What does it want with Alpha's life support core?
  4. Alpha's temperature meter is very crude (with 5 C intervals) and drops immediately.
  5. The robot is intelligent enough to fly an Eagle but stupid enough to chase television screens.
  6. Smashing the windows to escape, the Creature releases chlorine into Alpha's air circulation system.
  7. Why do the Alphans have Ionethermyecin, a drug "too powerful for humans"? Was it developed to attack aliens?


Chronology: 1503 days after leaving Earth orbit (Sat 25 Oct 2003)

Alpha Personnel: 1 fatality, Tom Graham.

Alpha Technology: In this episode only we discover that moonbase door controls can respond to verbal commands. Different Hydroponics units are seen in A Matter of Balance and The Troubled Spirit. The fixed laser cannons are seen. They are also in The Metamorph, Seed of Destruction, The Bringers of Wonder - Part 1 and The Dorcons. This is the first episode in which they are fired.

Eagles: Eagle 6 (Graham)

Maya transformations: Kreno animal (as in The AB Chrysalis), bee, lizard animal (as in Seed of Destruction), mouse (The Kreno animal from The AB Chrysalis is seen again. Unlike that episode, it is fine in normal air).

Planets: None

Aliens: The "Peculiar Cloud". The Creature is a robot, not a life-form.


  1. The Weapons section has a propogatoscope from A Matter of Balance.
  2. The vacuum chamber door in Int. Techlab 5 is the nuclear reactor door from Force of Life.


  1. It is asserted nothing can live in a vacuum. In Space Warp and The Bringers of Wonder - Part 2 Maya changes into space animals that can live in a vacuum.
  2. One shot of Eagle 6 returning to Alpha actually shows an Eagle leaving the base.
  3. When the travel tube doors close on the Creature, its hair is trapped


  1. The original script ran short and is padded with additional scenes of Fraser setting up the laser barrier and Tony and Maya firing the laser battery at the cloud.
  2. The script ended with Tony reading a magazine showing Catherine Schell as a model. Maya transforms into Catherine Schell and asks if he likes the look - he says yes. "Well, nobody ever accused you of having good taste." she says, and rips up the picture.
  3. The "mobile H T generator" that Fraser uses is a solid wooden box, 45cm x 25cm x 43cm (17.5" x 10" x 17"). It was for sale at a prop website in 2009 for £1495.

From Patrick Zimmerman: In the Butterworth novelization, it is Mark Macinlock that flies (and dies) in Eagle 6. Macinlock was the pilot intended to replace Alan Carter in year 2. In his adaption of The Metamorph, Butterworth erroneously used the name that appeared in the script; Macinlock, instead of Carter. Subsequent episodes used Carter, so this was a convenient way to kill him off. Interestingly, the Mark Macinlock character is used extensively in the first 4 German original Year 2 novels by H. W. Springer.


  1. See Alpha Date/Non Time Warp Date for a more detailed explanation of Second Season Story Dates.


Season 2
The Metamorph I The Exiles I One Moment of Humanity I All That Glisters I The Mark of Archanon I Journey to Where I The Taybor I The Rules of Luton I New Adam New Eve I Brian the Brain I Catacombs of the Moon I The AB Chrysalis I The Beta Cloud I Seed of Destruction I A Matter of Balance I Space Warp I The Bringers of Wonder - Part 1 I The Bringers of Wonder - Part 2 I Dorzak I The Seance Spectre I Devil's Planet I The Lambda Factor I The Immunity Syndrome I The Dorcons
Episodes are listed in the order suggested by Andrew Kearley.