Meglos

reTARDIS Season 18 20 September 2025 Hits: 433

The Doctor vs. a cactus with a superiority complex. Yes, really.

Short Synopsis

The Doctor and Romana get dragged into a power struggle between science and religion on the planet Tigella, while a sentient cactus named Meglos steals the Doctor’s face and tries to nab their power source.

Extended Storyline

On the lush world of Tigella, two factions are locked in a bitter rivalry: the Savants (scientists who love fiddling with wires) and the Deons (religious zealots who think plugging things in is blasphemy). Their entire society is powered by the Dodecahedron, a massive glowing crystal that conveniently looks like a rejected Dungeons & Dragons dice.

Meanwhile, elsewhere in space, the evil cactus Meglos has a plan. Yes, cactus. He’s a spiny green plant in a flowerpot who’s sick of sitting around photosynthesizing. Meglos wants the Dodecahedron for himself, and he’s not above a little face-swapping to get it.

Meglos enlists a band of bumbling mercenaries and a human “earthling” (random guy plucked from contemporary Earth, because why not?) to help him. He then uses his powers of plant-based possession to turn himself into… the Doctor. Cue Tom Baker acting extra sinister, with the occasional green spiny rash popping up on his face whenever the makeup team remembered.

The real Doctor and Romana arrive, only to be immediately caught in the middle of Tigella’s science-vs-religion culture war. The Savants want to study the Dodecahedron scientifically, while the Deons think it’s a holy relic that should only be worshipped. Neither side seems particularly good at noticing that their “Doctor” has all the warmth of a salad bar.

Meglos (as Fake Doctor) infiltrates Tigella, manipulates the factions, and makes off with the Dodecahedron, planning to turn it into the ultimate power source. Naturally, this involves a lot of monologuing and cactus gloating. Unfortunately for him, the Doctor and Romana escape long enough to expose the whole cactus-conspiracy.

The story climaxes with the Dodecahedron being destroyed (because of course it does — the BBC budget wasn’t about to fund a glowing d12 forever), leaving Tigella in chaos but also free from endless squabbles about it. Meglos, meanwhile, gets trapped and defeated — proving once and for all that the Doctor is no one’s succulent.

The Doctor and Romana scarper off again, no doubt relieved that their next villain might at least be something more dignified than a potted plant. (Spoiler: it won’t be.)

Episode: 111

Vital Statistics

Season: 18 (1980)
Episodes: 4
Doctor: Fourth
Companions: Romana II, K-9 (back from his saltwater holiday disaster)
Villains: Meglos the cactus, Tigellan mercenaries, bad theology

Fun Facts

Tom Baker plays both the Doctor and Meglos, making this the rare story where he argues with himself while covered in spiky green makeup.
Meglos’ possession of the “earthling” guest star was mostly an excuse to give an otherwise pointless human character something to do besides stand around looking confused.
Jacqueline Hill (the original Barbara Wright from the First Doctor era) returned to Doctor Who in this story — not as Barbara, but as Lexa, the high priestess of the Deons. She still got bossy speeches, though, so it felt right.
The mercenaries were dressed like the intergalactic rejects of a heavy metal road crew. They mostly served as comic relief and cannon fodder.

Viewer Reaction
Reactions range from “the one with the cactus is gloriously weird” to “what were they thinking?”. Fans generally remember it more for the novelty of Baker-as-a-cactus than for the actual plot.

💙💙Meglos proved that even an evil cactus can be scarier than most of Season 17’s monsters — and slightly less prickly than Tom Baker in his final season.