Attention all sections Alpha: we've recently experienced a collision course with a fantastic event - Space: 1999's 50th anniversary!

We asked you to pick your favourite episodes of Gerry and Sylvia Anderson's classic sci-fi TV series. We've collated your answers and are embracing the series' 50th celebrations by bringing you deep-dive listicles on your chosen episodes!

Our latest and final entry in our 10 Facts About... series of celebratory Space: 1999 episodes covers one of the most darkly horrifying adventures which the crew of Moonbase Alpha ever experience - Dragon's Domian!

Let's examine 10 fascinating facts about Dragon's Domain!

10. Penfold's departure

For many, Dragon's Domain remains Space: 1999's definitive combination of cosmic horror, character-driven drama and daringly futuristic adventure. Traumatised Eagle pilot Tony Cellini's nightmares return to haunt him when Moonbase Alpha encounters a terrifying graveyard of spacecraft that conceal a horrific monstrous presence. Tony may have survived his first encounter with the titular dragon, but will he survive twice?

Dragon's Domain was the final episode written by Space: 1999's story consultant, Christopher Penfold, to go into production. After the preceding Space Brain (also written by him) was completed, Penfold left the series, citing exhaustion at consistently having to meet the demands of ITC's executives in adjusting the scripts. Dragon's Domain was in a nearly complete state when Penfold left, and was subsequently put into production following Penfold's departure.

9. The original premise?

Despite having a minimal presence in the finished episode, Nick Tate would later claim that the role of the traumatised Eagle pilot Tony Cellini was initially meant for him, and that the whole episode was designed as a vehicle to advance Alan Carter's character. This was apparently vetoed by Martin Landau himself, who harboured anxieties in being overshadowed by his male co-stars on Space: 1999. The role was eventually given to Gianni Garko and became a convenient excuse for Italian co-financers RAI to include an Italian actor in the episode. Ironically enough, it was Tate who tutored Garko's improved English to prepare for the role.

8. Pre-Breakaway world-building

Dragon's Domain provides us with a tantalising glimpse of Moonbase Alpha's operations prior to the devastating Breakaway event - and the other missions of Alpha. Even prior to Alpha's benevolent purpose being subverted for the dumping of nuclear waste, it was evidently a hotbed of paranoia and tension. How many more ill-fated missions such as the Ultra Probe expedition, under Tony's command, has Moonbase Alpha borne witness to? The episode tickles the mind as to how many other power struggles that Moonbase Alpha has been a platform for.

7. Pre-Commander Koenig

A highlight of seeing the pre-Breakaway Moonbase Alpha in action are the brief snapshots of John Koenig prior to undertaking the command of Moonbase Alpha. Seen in the yellow-striped Alphan uniform worn by the likes of Alan Carter, it's a pleasing extension of the episode's world-building that we're permitted to see John Koenig before he became Commander Koenig. We see not the Commander Koenig laboured under the strain of safeguarding the Alphan men and women under his care. Instead, we see the relatively younger John Koenig fixated on helping out a troubled friend.

6. Storytime with Dr Russell

The first half of Dragon's Domain is framed as an extensive flashback sequence, bookended by narration from Dr Helena Russell, reciting the events for Moonbase Alpha's memory logs. This narrative tactic anticipates what would become commonplace throughout Year 2 - and not always to positive dramatic effect. Used in Dragon's Domain, however, Helena's softly spoken narration imbues the flashback sequence a bedtime story quality - quite appropriate for an episode liberated from the folk tale of St George and the Dragon.

5. Classical comparisons

Space: 1999's grandiose metaphysical adventure has consistently invited comparisons to the preceding 2001: A Space Odyssey, for many the ultimate experience in mind-bending science fiction cinema. Dragon's Domain strengthens the comparisons between the two with its usage of classical music. Where 2001: A Space Odyssey employs several pieces of classical music, Dragon's Domain effectively utilizes Adagio for strings and organ in G Minor for the Ultra Probe's lonely voyage into deep space. The piece had appeared in several films prior to Space: 1999 and was even desired by Gerry Anderson for 1969's Doppelganger. 

4. Susan Jameson's dual roles

Susan Jameson's brief but memorable appearance as Professor Juliet Mackie, one of the crew members of the Ultra Probe under Tony's command, wasn't her first foray into Gerry and Sylvia's cosmic futures. She also portrayed Anne Stone in UFO's The Sound of Silence. Despite her quite involved presence in that UFO episode, her role in Dragon's Domain amounts to becoming a swiftly consumed victim of the dragon's unstoppable hunger.

3. Spaceship graveyard

The titular dragon that consumes any lifeform who wanders into its path secretes itself within a haunting graveyard of spaceships. Many models used in previous episodes of Space: 1999 were used for these scenes, including craft first used in Collision Course, Voyager's Return, Alpha Child, War Games, and The Last Enemy. Model maker Martin Bower later claimed that models of the TARDIS from Doctor Who and the U.S.S. Enterprise from Star Trek were featured within this cluster, but these were removed from the finished episode. Ironically, the Ultra Probe model itself would be reused for the spaceship graveyard shots of Year 2's The Metamorph. 

2. Earth-based scenes

Circling back to how Dragon's Domain prizes open the pre-Breakaway world of Moonbase Alpha as a flourishing hub of humanity's great leaps into the stars, the scenes of Koenig, Bergman and Tony being questioned over Tony's actions in handling Ultra Probe's failed mission are the only scenes from Space: 1999's first series to be set on the then present day Earth.

There's the argument that we also see Earth in Another Time, Another Place, but where that doppelganger Earth is reduced to a post-Moon wasteland, ravaged by environmental effects of the Moon being torn out of orbit, these scenes remain a definitive snapshot of Earth.

1. Byrne's dogs

One individual who wasn't particularly traumatised by the dragon was script editor Johnny Byrne's male lurcher hound. Following filming of Dragon's Domain, the rubber-tentacled monster was dumped outside of Pinewood Studios, where Byrne frequented with his hounds. The male of the hounds couldn't resist urinating on the abandoned costume, leaving its territorial mark and undeterred by the dragon's terrifying form!

50 years since Moonbase Alpha was blasted out of the Earth's orbit, each and every episode of Space: 1999 is jam-packed with fascinating details involving their genesis, production and everlasting appeal. You can discover all of Space: 1999's secrets with our upcoming limited edition hardback, All Sections Alpha: The Making of Space: 1999 by Fred McNamara and Tim Heald.

Celebrate Space: 1999's landmark anniversary by also checking out our previous episode listicles - The Metamorph, Breakaway, The Bringers of Wonder, The Last Sunset, and Black Sun. You can also catch up on our colossal celebratory retrospective of the series, watch the brand new documentary on ITVX (Space: 1999: 50 Years Out of Orbit), and discover our Breakaway Collection 2025 for more spectacular releases marking half a century of the adventures of Moonbase Alpha!

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