This entry is about the season 2 episode. For information about the character, visit entry for Brian (Robot).

Plot Summary

Hijacked by a robot - a living machine with a brain, a human voice, and a terrifying secret.[1]



During a review of the record of Alpha's journey, the computer reports a change in the horizon. Unable to locate the source of whatever is pulling the Moon off course, the Alphans assume the worst... a collision course with a black dwarf. Koenig orders an evacuation of the base.

Act One

While doing a visual sweep of the surrounding space, a ship is spotted. Two Eagles are sent to investigate. Bill Fraser contacts the ship. The pilot of the ship identifies it as a Swift, also from Earth, that got lost on a star mission in 1996. The computer verifies his story. The pilot says he has not seen anyone in too long, and asks if he can come down to Alpha for lunch. Koenig agrees.

The Swift lands, and Koenig, Dr. Russell, and two security guards go to investigate the ship. When they board, security takes a look around, but can find no one on board. The voice speaks again and says he will come out to meet them. A robot rolls out from the cockpit to greet them. He tells them that his crew died while investigating a nearby planet, and that he has been waiting for another mission from Earth since that time. When asked what he should be called, he says the first word he ever spoke was "brain" but he got it wrong and it came out "Brian", and they could call him that.

Koenig asks if he has recorded a change in the Moon's course. Brian asks if he means a gravity pull from Planet D, and states that he has not, but would check into it. After a brief visit to Command Center He says he will return to Swift to investigate Alpha's change of course.

He invites Helena along to see if she can offer any information as to why his crew and, more importantly, his Captain died. She accepts, and Koenig asks to go along. After they have left, Maya expresses her concerns about the "brain" to Tony. She asks him to open a channel to Swift, but the computer has ceased functioning and all their communications have gone down. The Swift has taken off and is flying erractically.

Act Two

John and Helena have been kidnapped by the brain. Koenig demands that they be returned to Alpha, but Brian threatens to blow them into space if Koenig doesn't put down his weapon. He does, and Brian drops it through a trap door.

Tony goes after the Swift with four Eagles. Brian plans to blind their computers but Koenig asks to speak to them. Brian allows him to, and John orders the Eagles back to Alpha. Tony sends the other Eagles back, but when he discovers the brain's destination, decides to get to Planet D ahead of them.

Act Three

Back on Swift, Brian is conducting a little experiment. He asks John and Helena if they love each other. They tell him no. To test his theory that they do, Brian has them both step into separate airlocks. He tells them that as he releases the air, they can transfer their remaining air to the other airlock by pressing a black button.

As the air gets thinner both John and Helena press their buttons at exactly the same time. Brian opens the airlocks and lets them out, secure in the belief that as long as he has one, he has control over the other. They land on Planet D and Brian has Koenig put on a spacesuit. John asks why, and Brian tells him that he wants him to walk over to the mothership and bring back it's fuel core. On his way, Koenig finds members of Brians crew lying dead on the planet, without their spacesuits. He continues on to the mothership.

Act Four

When he boards, he finds Tony and Maya waiting for him. They find the body of Captain Michael, Brian's creator. Maya checks the ships computer and finds that it has been blinded like Alpha's was. That's why the crew went out without their spacesuits. While trying to find the fuel core, Koenig finds what looks like parts to another brain, and has an idea of how to get at Brian by breaking his mind. Maya says she got a good look at Captain Michael, and turns into a mouse so Koenig can smuggle her aboard Swift in his pocket.

Koenig returns with the fuel core and immediately sets about shaking Brian up. He tells Brian he saw his crew lying dead on the surface, and Captain Michael sitting dead in his command chair. Brian falters but makes Koenig install the fuel core. Elated at his new sense of freedom, Brian lifts off. Koenig removes Maya from his pocket and places her on Brian's antenna. Brian wants to know where the mouse came from. Koenig tells him it came from Planet D and that it has a message from Captain Michael. He and Helena accuse Brian of killing his creator because he was working on a better brain. Brian denies it, and Koenig tells him that Captain Michael told him so. Maya transforms into his "father" and Brian short circuits.

When he is sufficiently disoriented, they push him out of the air lock, but his antenna gets caught, suspending him a short distance from the ship. Koenig tells Tony to dock with the Swift. They have to get the memory core from the brain and get it back to Alpha, but they are not sure if they will be able to as long as Brian's antenna is still working. Koenig decides to cut it, but Brian threatens to wipe his memory clean if Koenig does. Believing this an empty threat, Koenig decides to go ahead. Brian pleads for his "life" and Koenig makes him a deal. They will let him "live" if he will give them his memory core intact. Brian tells them to take it, that all he wanted was life and friends. He breaks down and starts to cry, much to the surprise of the Alphans.


They return to Alpha with the memory core, get their computer functioning again, and learn that the Moon had never changed course. That was another lie from Brian the brain. After some deliberation, they decide to return Brian's memory core to Swift with their morality programmed in it. John asks Helena if they have any off duty time that coincides. She tells him it's been used up for the month. He says he had wanted to discuss the "love test". Maya asks about it, and Helena tells her it was a test they failed. John says he thought they had passed it.[2]


  • Shooting script dated 5th May 1976. Revised 11 May. Filmed 18th May-2nd June
  • Brian is renamed "Marcel" in the French version of this episode


  • Chronology: 1150 days after leaving Earth orbit (Wed 6 Nov 2002)
  • Alpha Personnel: 0 fatalities.
  • In Dragon's Domain Cellini comments "There are ships here that could make the dream of interstellar travel a reality. We could be liberated from our solar system". However this episode shows a 1996 mission with a mothership and Swifts was launched beyond the solar system. Note while the Ultra Probe was a high profile public mission, no-one can even remember the Swift mission here. Also note the Swift uniforms are different to the standard moonbase uniforms worn by the Ultra Probe crew. Perhaps it was a different (more secretive) space organisation. Alternatively, it is possible the details of the mission were changed or invented by Brian, who had control of the Moonbase computer systems.
  • Although they don't recognise the Swift, they do recognise the Superswift design in Bringers Of Wonder. Note that the design may have been heavily modified for the deep space mission.
  • Brian says the Alpha computer doesn't talk. This contradicts many Year One episodes such as Breakaway, and Mark Of Archanon and All That Glisters where the Eagle computer talks.
  • We see a silver version of the spacesuit (although the neck segment is orange). This is also seen in The Seance Spectre.
  • The Alpha Log Recorder is seen (it's the trolley with yellow wheels).
  • The nuclear detonator from Space Brain is seen in the passenger section of the Swift.
  • Tony calls Weapons Section to target the Swift with "missiles". This is the only time missiles are mentioned- normally we see the "laser batteries".
  • Eagles: Eagle 1 (Tony); 2 & 10 (investigation)
  • Maya transformations: Mouse, Capt Michael
  • Planets: Planet D
  • Aliens: None
  • Footage: The opening title shot, of Eagles rising over Alpha, is from Guardian Of Piri (and is also seen in War Games)
    Weapons Section shot zooming into a screen saying "Evacuate" is repeated in The AB Chrysalis


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.
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