“Telepathic potato people who are afraid of the dark.”
Short Synopsis
The Doctor and friends land on a spaceship trapped in orbit around a planet full of nervous, mind-reading aliens. Cue paranoia, politics, poisoned water, and the Doctor wielding a stethoscope like a weapon.
Extended Storyline
The TARDIS drops our heroes onto a seemingly abandoned spaceship orbiting the Sense-Sphere. Inside they find a crew of humans who are alive, but so blank-faced you’d think they’d all been hypnotized by an especially dull PowerPoint. Turns out they have been brain-meddled by the Sensorites — bald, wide-eyed aliens with beardy chin-straps and the general vibe of “psychic pensioners.”
The Sensorites themselves arrive looking twitchy, mumbling about how humans are a “threat” because once some miners came to steal their molybdenum (yep, that’s the plot MacGuffin). They can read thoughts, but unfortunately their main weakness is that they all faint dead away in the dark. Imagine a whole planet of people who forget to bring night-lights. Terrifying, right?
The Doctor decides the best way to handle things is by aggressively waving his cape around and diagnosing everyone with science. Barbara gets shoved into the background (vacation time for Jacqueline Hill), Ian drinks poisoned water and spends two episodes doing a very convincing impression of a flu-ridden substitute teacher, and Susan suddenly remembers she has telepathy and starts chatting with the aliens like they’re her long-lost pen pals.
Things escalate into political intrigue: there’s a paranoid City Administrator (the only one who thinks “evil plan” is a valid career path), power struggles, water contamination sabotage, and an entire subplot about who gets to wear the special collar that says “I’m in charge.” Eventually, the Doctor exposes the baddies, cures the poisoned water, and lectures the Sensorites about not being xenophobic hermits.
Before leaving, he drops his stethoscope like a mic. The crew runs back to the TARDIS, only mildly traumatized, and the audience is left wondering why molybdenum is suddenly the most precious element in the galaxy.