All Alphans except Koenig fall under the spell of a massive computer on the planet Piri, which has given them eternal happiness.
OH THE NOSTALGIA! There are a couple of patented Koenig back-handed slaps in this episode, which is largely what I remember Space 1999 action scenes to be like when I was a kid.
REVIEW: Space 1999 does the Lotus Eaters, or more likely Star Trek's This Side of Paradise, though in a more modern idiom, it could be a drug story. The Alphans all end up blissed up and tuned out on the planet surface, while Koenig is up on the Moon alone taking uppers to stay awake. If it IS a drug story, I'm not sure on what side of the issue it stands. On the issue of weird nonsense, however, it stands resolutely for it. The planet Piri's weird landscape was at least "built" by some lost civilization, the status of which is meant to be a twist, but it's just about the most obvious thing about the script. The Guardian itself is a giant machine that looks like a great big web of spheres, and blows up when somebody makes arguments at it, just like a Star Trek computer. Well, no, I'm kidding. Koenig's speeches don't really make a dent. It's only when he shoots the Guardian's beautiful messenger - played by a wasted Catherine Schell who doesn't appear nearly enough - in the face (gory even if she is a robot) that it blows itself up. Why exactly? I don't know. I'm still trying to figure out why Koenig is the only Alphan with ANY measure of willpower.
On that count, we might refer back to earlier episodes where Alphans, Koenig included, deferred decisions to the computer. This theme is brought back in this episode, as the computer becomes unreliable, but then so do human brains under the Guardian's influence. The Alphans, even the ones like Alan who railed against over-reliance on the computer, eventually trade one master for another, and let the Guardian make their decisions for them. Obviously, Kano is going to be the one defending the computer the most, and here we discover his bond with technology is tighter than we thought. He was once part of an experiment that allows him to jack into the computer directly. Since he was the experiment's only survivor, he's not eager to try it again. Will this become a recurring element as the series forges ahead? I somehow doubt it. But that's the extent of the character development in Guardian of Piri, because everyone is somewhere between elation and euphoria. Helena is irritatingly giggly, at least until Koenig gives her electroshock therapy (sheesh!). They're not themselves, and soon become a bare-chested mob trying to kill Koenig.
I will still give props to director Charles Crichton for some creepy shots of the empty Moonbase and of the Alphans ignoring a wounded Koenig while they party on, dude. Hopefully, the Guardian healed all those dying people Helena seems to always have hidden away in the medical bay either before or after Koenig was left to rot in orbit. Crichton is less successful with the big storm of soap bubbles, glitter and packing peanuts at the end, but he had to do something with the notion that plant life would thrive as soon as "time resumed". The end note is the lame irony that Piri might have become habitable once the Moon left.
HEY, ISN'T THAT... Catherine Schell is the Pirian girl; she would of course return in Season 2 as a regular cast member, i.e Maya, and was the beautiful-probably Countess in Doctor Who's City of Death. Michael Culver is goofy pilot Pete Irving; he was Captain Needa in The Empire Strikes Back. If the planet Piri looks familiar, it's because it was also seen in Doctor Who's Nightmare of Eden (just like the one in Matter of Life and Death).
REWATCHABILITY: Medium-Low - One of those episodes that feels like they just put a few original Star Trek episodes in a blender and pressed purée, then sucked all the juice out of it.