Episode QuoteEdit

"This is the voice of Voyager One. Greetings from the people of the planet Earth."

Plot SummaryEdit

Grim danger emerges from the past. Moonbase Alpha is threatened with destruction from an unmanned spacecraft sent up from Earth many years earlier, with tragedy in its wake. Even worse lies ahead from outer space victims seeking revenge.[2]


Two Eagles are sent out to investigate an object approaching the Moon just beyond sensor range. As it gets closer, Computer identifies it as a powered craft. Alan's Eagle detects a signal being transmitted by the approaching vessel. Koenig has him relay it to Alpha. When they respond to the ship's signal. it identifies itself as Voyager 1, declaring that it is unmanned, unarmed and comes in peace. Koenig immediately orders Carter and Abrams to get away from it. Alan manages to pull away, but Steve Abrams' Eagle begins to break apart from the forces generated by the Voyager craft, and is unable to. In Main Mission, they watch helplessly as Abrams' Eagle explodes, while listening to Voyager 1 broadcast cheerful greetings from the people of planet Earth.

Act OneEdit

Alan contacts Alpha and asks what hit them. Koenig tells him it was the Queller Drive, and orders him back to base. Koenig explains that Voyager 1 was equipped with the Queller drive enabling it to move across space at incredible speeds. Paul elaborates, stating that it achieves these speeds by spewing out fast neutrons which annihilate anything in their path. Victor prints out information about Voyager and it's mission.

It was launched in 1985 "to probe the galaxy for signs of intelligent life, find habitable solar systems, and make man's presence known in the galaxy". Victor is giddy with the idea of the data Voyager has collected. But Paul and Helena are more concerned about the imminent danger that Voyager 1 poses to Alpha. John brings Victor and Helena into his office to discuss the matter further. After establishing that Voyager 1 has chemical rockets, as well as the Queller drive; and that there is some chance of safely landing the ship and saving the valuable information on board, John decides they have to try.

Word spreads through the base that a Voyager ship is approaching, and that there is an attempt to try to land it. Jim Haines passes this information on to his mentor, Dr. Ernst Linden, who reacts with dismay, and immediately leaves saying "They can't do that." to himself. He arrives in Main Mission, where they are having no success in overriding Voyager's command codes. As Victor is stymied for an answer, Dr. Linden steps forward, and states that there is a way to do just that. But if the command is not preceded by the most precise signal the ship may self destruct. When Koenig asks how he knows this, Dr. Linden tells the Commander that if he checks his personnel file, he will see that his name was once Queller. He was the man who designed the Queller drive on the Voyager ship approaching Alpha.

Act TwoEdit

Koenig has a command conference to decide how to proceed. When Linden's real identity is revealed, there is shock and outrage among the members of the conference. Alan, because Steve Abrams died due to the Queller drive on Voyager 1. Paul, even more so, because his father was one of 200 hundred people, who died fifteen years ago when Voyager 2 launched, and the Queller drive cut in too early. Despite all of this, Koenig decides to talk to Linden to see if he will be able to bring in Voyager 1 safely.

Linden is brought in, and asked if he can override Voyager's onboard computer, and shut down the Queller drive with the materials available to him on Alpha, within the time (9hrs 10 mins) left before Voyager 1 gets close enough to become a threat, and has to be shot down. Linden replies that it is possible. When Koenig tries to get a definite "yes or no" from him, Linden tells him that 20 years ago he would've given his guarantee, but now, he can only say that he will do his best. Linden is excused, and Koenig decides to give him the chance. Paul is instructed to keep Linden's identity secret, even from Jim Haines, who lost both his parents to the Queller drive.

Work begins, and Linden tells Victor that for years he has thought about why the Queller drive did not disengage near populated areas, and must proceed from the assumption that his theories are right. Several hours later Koenig checks on Linden's progress. Linden is certain that he will be able to accomplish his task. Meanwhile, Alan has prepared a back up plan to have three Eagles standing by to shoot down Voyager should Linden fail. Those Eagles lift off to designated coordinates to await Voyager. With one hour left, Linden and Jim Haines have recreated the circuit which will override Voyager's computer. When Jim realizes that only one man had the knowledge to do this, he confronts, and attacks Queller, damaging the equipment they had just completed.

Act ThreeEdit

Queller is revived, and despite several cracked ribs, asks if he can try to repair the damage in the 35 minutes left before Voyager is shot down. Koenig gives him the ok, and asks Helena to keep him going. Koenig receives an urgent call to return to Main Mission. Three ships are following Voyager, and are on a course towards Alpha. Voyager 1 has passed the safety zone, and Alan is waiting for Koenig to give the order for his men to shoot it down. Koenig tells Alan to wait. Queller contacts Main Mission and says that he is ready. Kano links Queller's command circuit to main computer, which allows Queller to shut down the Queller drive, and land Voyager 1 on launch pad 4. Queller thanks Koenig for giving him the chance. While Main Mission monitors the three approaching ships, Koenig, Helena, Victor, and Queller board Voyager 1. Queller starts to give them a short tour of Voyager when Koenig receives a message from Paul warning of a magnetic build up on Voyager.

Act FourEdit

The image of an alien appears and introduces himself as Aarchon, the Chief Justifier of the Federated Worlds of Sidon. He asks if they are citizens of Earth. Koenig says that they are. Aarchon asks if they accept responsibility for Voyager 1. Koenig tells him they do. Aarchon replies that they, along with the rest of Earth, must bear the judgment of Sidon. He explains that Voyager 1 came proclaiming peace, and was welcomed by his people, but when it came into contact with two of their populated worlds, it extinguished all life on them. To ensure that this never happens again, three war ships have followed Voyager to find it's planet of origin, and destroy it. Not willing to accept this lying down, Koenig orders Carter to move Eagles 4, 6, and 10 to intercept the Sidon warships.

In Medical Centre, Queller is recovering from his wounds. He tells Helena that he is very upset to find that after years of thinking he had helped to expand the boundaries of man's knowledge, that he is responsible for rendering two planets lifeless. He tells her it is a burden that he must bear alone. Victor presents John with the memory banks from Voyager 1, but laments that they may never get the chance to use the information. Helena joins them, and asks John what he thinks their chances are. He tells her a thousand to one.

Queller dresses and leaves Medical Centre, heading to the experimental labs. He activates the command circuit, and heads down to the embarkation area. Jim Haines enters the lab, and sees that the command circuit has been switched on. He catches up to Queller just as he is about to enter the travel tube to Voyager 1's launch pad. Queller asks Jim not to try to stop him. Jim replies that he's going with him. Queller tells Jim that it is something he needs to do alone. Jim silently let's Queller go. Helena realizes that Queller is missing from Medical Centre as he boards Voyager 1. Paul alerts Koenig when he detects Voyager's unauthorized launch.

Queller contacts Main Mission, and tells Koenig to recall the Eagles, and put all Alpha's screens on maximum. Koenig tells him that the Eagles are all that stand between the Sidon ships and Alpha. Queller tells him that the Queller drive is the only effective thing between them. Koenig realizes this is true, and has Alan recall the Eagles. Aarchon appears on the big screen, and tells him that since they chose not to resist, the manner of their destruction will be merciful. Queller interrupts this message to tell Aarchon that as the designer of the Queller drive, he alone should be held responsible for the damage it has done. He pleads Aarchon not to punish innocent people for his mistakes. When Aarchon dismisses him out of hand, and continues with his plans to destroy Alpha, Queller activates the Queller drive in short bursts. This causes the Sidon ship to weaken, and when Queller activates Voyager's self destruct mechanism, he takes the Sidon warships with him.


Koenig enters the Experimental Lab as Jim Haines destroys the command circuit he and Queller worked on. Jim Haines is upset because he feels he spent so much time getting to know and respect Linden, only to find that he didn't know him at all. Koenig tells him that the man was exactly the same. Only his name was different. He says that Queller sacrificed his life to give them a chance. He hands Jim the data bank from Voyager, and tells him that if he respected the man, not to let his sacrifice be in vain.[3]


Filming ScheduleEdit

Wednesday, August 7th - Monday, August 26th, 1974


This episode marks the series debut of director Bob Kellett, the temporary replacement for David Tomblin while he was engaged on Barry Lyndon (1975). Kellett made a noted film debut as the director of A Home Of Your Own (1964), but prior to his Space:1999 work he was best-known for a series of bawdy comedies, including Up The Chastity Belt (1971), Up The Front (1972) and The Garnett Saga (1972). Post-1999, he directed Spanish Fly (1976) and Are You Being Served? (1977).

Some of the incidental music in this episode was originally composed by Barry Gray for the Thunderbirds episode 30 Minutes After Noon, the Thunderbird 6 feature film and the The Secret Service episode Last Train To Bufflers Halt.


  1. Image of the three Sidon ships in flight is from Reflections on Film and TV

Season 1
Breakaway I Earthbound I Black Sun I Missing Link I Voyager's Return I Matter of Life and Death I Ring Around the Moon I The Last Sunset I Alpha Child I Death's Other Dominion I Force of Life I Guardian of Piri I The Troubled Spirit I The Last Enemy I Collision Course I Dragon's Domain I The Full Circle I Mission of the Darians I End of Eternity I War Games I The Infernal Machine I Another Time, Another Place I Space Brain I The Testament of Arkadia
Episodes are listed in the order suggested by Andrew Kearley.
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