Space exploration meets Cold War paranoia, with added radiation zombies in astronaut suits.
Short Synopsis
When a British space mission goes radio silent, the Doctor and UNIT investigate. The astronauts who return are not what they seem — glowing, radioactive aliens in disguise — and humanity does what it does best: panic, kidnap, and bungle diplomacy.
Extended Storyline
It all kicks off with Mars Probe 7, a mission that’s gone suspiciously quiet. When Earth finally reestablishes contact, the astronauts aboard don’t sound quite right. The Doctor smells something fishy, and it’s not just the BBC’s sound effects department.
Enter a rescue mission — Recovery 7 — which manages to bring the astronauts back to Earth. Except… surprise! These aren’t astronauts at all, but radioactive alien ambassadors who look like astronauts but wander around killing people with a single touch. It’s not their fault — it’s just what happens when you shake hands while emitting lethal doses of radiation.
Naturally, instead of telling the public the truth, UNIT tries to contain the situation. Enter General Carrington, a man who thinks the best way to handle delicate extraterrestrial contact is with paranoia and violence. His brilliant plan? Kidnap the alien ambassadors, keep them locked in spacesuits, and use them as propaganda tools against alien invasion. (This is why we can’t have nice things in space.)
The Doctor, of course, argues for peace. He learns the aliens themselves are actually peaceful explorers, furious that their ambassadors have been turned into unwitting murder machines thanks to Carrington’s interference. They don’t want war — they just want their people back.
Cue seven episodes of running between warehouses, rocket launchpads, and the odd bit of lab tinkering. Liz Shaw spends much of her time being kidnapped (again), and the Doctor spends his time toggling between exasperation with UNIT and smugness when his predictions about human stupidity come true.
In the climax, the Doctor exposes Carrington’s plan to stage a fake alien invasion. The general is revealed as more misguided than malicious, and is led away with the promise of “understanding” rather than punishment. The aliens get their ambassadors back, and Earth avoids interstellar war… at least until the next time.