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 entry sees Moonbase Alpha encounter something bizarrely frightening and grimly incomprehensible - Year 2! The crew of Moonbase Alpha undergo an extreme makeover for Space: 1999's second series; but that's not the only surreal experience to be found in The Metamorph. Within the dying planet of Psychon, the maniacal Mentor seeks to rejuvenate his failing world with the unwitting help of the Alphans. Can his beautiful shapeshifting daughter save the Alphans from Mentor's wicked plans?

Let's examine 10 fascinating facts about The Metamorph!

10. Returning guest stars

The Metamorph opens Year 2 of Space: 1999 with a pair of recognisable faces. Catherine Schell had previously portrayed the siren-like guardian in Guardian of Piri, while Brian Blessed had portrayed the human scientist Cabot in Death's Other Dominion. The Metamorph sees both actors return to portray equally cosmically memorable roles in Space: 1999.

9. Johnny Byrne's original script

The Metamorph was the first of three episodes of Space: 1999's second series written by Year 1 script editor, Johnny Byrne. He, along with story consultant Christopher Penfold, wrote and edited much of Year 1 between them, and were crucial voices in shaping the metaphysical philosophy of Space: 1999. Byrne's original script for what would become The Metamorph was written in the Year 1 format - and was forced to undergo significant changes to meet Year 2 producer Fred Freiberger's new demands.

The Biological Soul was written initially without introducing Maya. Byrne's original script focused far more on the folly of Mentor's obsession with bringing his dead world back to life, merging elements of War Games and The Infernal Machine. Later retitled The Biological Computer to introduce Maya, the script was ultimately overhauled entirely to allow for Maya's intro to become the overriding focus of the episode.

8. Changes in Moonbase Alpha

One of Year 2's most infamous slights against Space: 1999's first series is the sudden onscreen reinvention of Moonbase Alpha. The sprawling Main Mission hall has been downgraded to become the rather more compact Command Center, while the unisex Alphan uniforms are added with multi-coloured jackets. These cosmetic changes make their debut in The Metamorph, but none of them are commented upon in-universe.

7. Laser cannons

Another abrupt addition to Moonbase Alpha's defensive set-up is the inclusion of laser cannons, seen here in The Metamorph for the first time. These devastatingly powerful weapons were never seen or heard of in Year 1. Prior to the Breakaway event, Moonbase Alpha was never intended to be a strategic battle platform in mankind's conquest of the stars. Intriguingly, the idea of mankind's first base on the Moon being armed with defensive weaponry was a feature of the original Zero G script outline by Gerry and Sylvia Anderson, written before Year 1 went into production.

6. Date format

As the opening episode of Year 2, The Metamorph is the first episode to open with the contextual date format that now kickstarts the beginning of nearly every Year 2 episode. Stories would now open with status reports, conducted by Dr. Helena Russell. They serve little in-universe purpose, but otherwise act as expositional dump to clue the viewer into the early scenario of any given episode. It would prove to be just one of many elements that Space: 1999's second series liberally borrowed from Star Trek.

5. Cosmic Princess

Much like Breakaway, The Metamorph has been subject to plenty of interpretations in other media. Its most significant 'other' outing was its combination with the later Maya focused episode Space Warp to become the 1982 compilation film Cosmic Princess. This was the last of the four Space: 1999 compilation films from ITC and liberally chops up both The Metamorph and Space Warp to frame the two episodes as an uninterrupted event, presenting the effects experienced by Maya in Space Warp as occurring as a result of the events of The Metamorph.

4. Comic adaptations

The Metamorph was also subject to a pair of comic strip adaptations from Charlton Comics. The US-based publisher had launched a pair of Space: 1999 comics to tie in with the release of the first series. The Space: 1999 comic was aimed at a juvenile audience, while the Space: 1999 comic magazine was targeted at an older demographic. Both comics mostly prioritised original storylines, but The Metamorph was adapted in both publications. Garry Morrow illustrated the comic magazine adaptation, while Pat Boyette illustrated the comic version.

3. Spaceship graveyard

The Metamorph is the second episode of Space: 1999 to feature the frightening depiction of a spaceship graveyard, something first seen in Year 1's fan-favourite Dragon's Domain. The sprawling array of obscured craft seen in The Metamorph are reused alien craft and Alphan technology from Dragon's Domain, Collision Course, The Last Sunset, Voyager's Return and The Last Enemy.

2. Beginning of Psychon trauma

The Metamorph is the first episode in a loosely defined story arc that bubbles beneath the surface of much of Year 2 that grapples with Maya's lingering trauma at being the only living Psychon left in the universe. New Adam, New Eve, The Rules of Luton, Space Warp, Dorzak and The Dorcons all spiral out of the events of The Metamorph, showcasing varying explorations of how Maya deals with being the last Psychon left. Sometimes this trauma is at the centre of the episode's drama and action, such as The Dorcons or Dorzak, whereas in New Adam, New Eve and The Rules of Luton, it's played more as a background detail that nonetheless offers a welcome insight into Maya's state of mind.

1. Unaimable lions

Maya's transformation to and from a dangerous lion may be a delightfully fun introduction to her metamorphic abilities. But behind the scenes, the inclusion of a very real wild animal on the Pinewood set brought a number of complications - specifically, just how many lions the episode had to go through! 

Several lions were used during the filming of The Metamorph, all with mixed results. The first lion used was far too untamed to interact with its other, more human actors. The second lion proved to be another casualty in Space: 1999's list of actors who proved difficult to work with. It wasn't cooperative during filming owing to toothache. The third and final lion used proved overly aimable, putting its paws on the shoulders of the still photographer, but at least the creature was pleasant enough to allow production of The Metamorph to continue without further incident!

Celebrate Space: 1999's 50th anniversary with our Breakaway Collection 2025! Whether it's the definitive behind-the-scenes story of Moonbase Alpha or the ultimate high definition viewing experience of Breakaway, we have a fantastic range of releases for you to enjoy!

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