[3] The Moon is travelling through a binary star system, where sensors detect a habitable planet supporting an advanced civilisation.

As the mood on Alpha grows apprehensive, tracking radar picks up three objects speeding toward the Moon without advance warning from long-range scan.

With recognisable war machines approaching from an unresponsive planet, John Koenig deploys Combat Flight One.

Moonbase Alpha mobilises for battle: Combat Flight Two is put on stand-by, defence screens are activated, and rescue and emergency medical units prepare for action.

The interlopers continue to close on Alpha; just before they can move out of the Eagles' weapons range, he gives the order to fire.

After Carter expresses concern that his victory was too easy, a second Hawk squadron is detected approaching from the opposite direction.

Eagle Four has barely cleared Alpha when it is struck; debris from the explosion smashes into the Main Mission building, bringing the ceiling down on the staff.

Sandra Benes has his answer on the big screen: a massive (and oddly familiar) space battleship is approaching, accompanied by a flotilla of Hawks.

Carter knows he is the only one who can prevent the coming massacre; he and co-pilot Pete Johnson power up and fire a concentrated laser charge at the dreadnought.

All vital systems—food production and recycling facilities, water purification plant, main generators—are heavily damaged and will require weeks to repair...but only eight days of battery power remain.

With Paul Morrow broadcasting their peaceful intent, Koenig and Helena fly down in an unarmed reconnaissance Eagle to attempt to open a dialogue with their aggressors.

Koenig accuses the alien of ignoring their peaceful hails, launching an unprovoked attack, and leaving them without the means to live.

He records a poignant message for any future travellers that might land on the wandering Moon, giving a brief history of their voyage and their uncertain fate.

The complex around her is a macro-brain, developing and growing with each generation of attendants who reside within and fed by the life-force of the collective population.

Struck by a sudden flash of insight, he commands Carter to stand down...after which the Hawks literally vanish from existence.

To keep them away, the aliens' only defence was to make the Alphans' worst fears appear real—the Hawks, the dreadnought, the planetary force-barrier.

In addition to the regular Barry Gray score (drawn primarily from "Breakaway" and "Another Time, Another Place"), Mike Hankinson's composition 'The Astronauts' is used during the dogfight sequence as well as the Alpha attack scenes.

Along with "Black Sun" and "Collision Course", it is considered to be one of the programme's most successful installments by actors, production staff and fans alike, exemplifying Space: 1999's metaphysical approach to science fiction.

[3] ITC's New York executives initially rejected the script as it seemed to them to kill off members of the regular cast; it was finally approved for production after Penfold explained the ending.

[1] At this point, frustrated at the direction he felt ITC's creative decisions were taking the show, Penfold began to consider leaving the series.

He felt mankind could be seen as an invading virus, spreading destruction in space akin to the Spanish conquistadores' devastation of the New World.

[3] Barry Morse felt it showcased George Bernard Shaw's belief that mankind's worst destructiveness comes either through anger or from fear, which usually prove to be without foundation.

[5] Actress Zienia Merton affirms this episode furthered her belief that director Charles Crichton owned significant shares in the company which produced Fuller's earth, the dust-like substance used in films to simulate explosions, create sand- or dust-storms, or age props or costumes.

After the dust-storms in the Crichton-helmed "Matter of Life and Death" and "The Last Sunset", the product was mixed with falling debris during the attack on Alpha.

Merton avoided the mess by diving under her desk; others, including Martin Landau and Prentis Hancock, were not as fortunate.

[6] The alien battleship seen here, designed by Martin Bower, made its debut in the episode "Alpha Child"; it would later appear in "Dragon's Domain" and "The Metamorph".

The aliens' transparent column-habitats would be re-vamped into growing compartments for "The Troubled Spirit" and other episodes set in Alpha's Hydroponics department.

In response to concerns that it would appear too similar to the Eagles when filmed, Bray Studios technician Cyril Foster hurriedly painted orange details on the miniatures before the shoot.

Although it praised the episode's special effects and "sense of desperation", TV Zone magazine rated "War Games" the worst instalment of Space: 1999's first series, commenting that its use of illusion as a narrative technique "feels like a cheat" and criticising the "frankly bizarre" guest performances of Blair and Valentine, describing these as "a textbook example of how not to 'act alien'.