"Well, to be fair I did have a couple of gadgets which he probably didn't, like a teaspoon and an open mind."
— The Doctor explains how he learned more about the egg in minutes than local scientists did in years
The TARDIS follows a distress signal
to the planet Chloris, where the Doctor and Romana investigate what appears to be the shattered remains of an enormous metal egg. (The Doctor's technique largely involves listening to the sound made when he taps it with a teaspoon.) They are captured by guards and taken to see the local dictator, Lady Adrasta, who owns the mine that is the planet's only source of metal. Adrasta is impressed by how much the Doctor has figured out about the egg, and wants him to work for her; the alternative is to be thrown into the Pit, an abandoned mine working inhabited by a mysterious Creature that kills all who come near.
The Doctor being the Doctor, he jumps into the pit with both feet, and soon meets the Creature. It can't talk, so the Doctor resorts to cuddling with it and extensively putting his mouth on its... large bits that stick out
. Once the Creature manipulates some local beardy men into retrieving its communicator, it's able to use the Doctor's own voice to speak, and the Doctor discovers that it is in fact an alien ambassador from the planet Tythonus, whose spacecraft was the egg investigated earlier. Tythonus has lots of metal but not much vegetation, and the ambassador had hoped to organise a trade, and was thrown into the pit for his trouble — Adrasta's stranglehold on metal production is keeping her in power.
The Doctor helps the ambassador to escape, and in return the ambassador helps the Doctor to divert the neutron star that the Tythonians have aimed at Chloris in retaliation. Adrasta is killed by the ambassador, and a trading contract is drawn up.
- Astrologer: Organon was an itinerrant Court Astrologer, until Lady Adrasta threw him down the pit.
- Big "NO!": Adrasta at the pt. 3 cliffhanger.
- Crazy-Prepared: parodied.
- Curse of Babel
- Distress Call
- Exactly What It Says on the Tin: There's a running joke about the straightforwardness with which Adrasta names things: There's a creature, which is called "the Creature", in a pit, which is called "the Pit", and also a place that's an automatic death sentence for anybody found there, which is called "the Place of Death".
- Famous Last Words
- Lady Land
- Million-to-One Chance
- Never Tell Me the Odds
- Only Electric Sheep Are Cheap: In an inorganic variant, the bandit chieftain waxes rhapsodic about the amazing treasures his group has stolen: precious items of iron, zinc, and even nickel! Needless to say, this scene takes place on a metal-poor planet, where only members of the elite can boast such prizes.
- The Other Darrin: K-9, who now has a different voice after being temporarily put out of action by robo-laryngitis earlier in the season. In real-life, previous voice actor John Leeson had quit the series and had been replaced by David Brierly.
- Phony Psychic: Organon
- Plant Aliens: The mobile, carnivorous wolf-weeds.
- Sickly Green Glow: The Creature; more or less justified by its Bizarre Alien Biology
- Single-Biome Planet: The jungle world of Chloris
- Stellar Name: "Adrasta" is one letter off "ad astra", Latin for "to the stars" (as in "Ad astra per aspera", "A rough road leads to the stars", the state motto of Kansas).
- Terms of Endangerment: Adrasta rarely misses a chance to call Romana "my dear", usually while simultaneously holding a sword to her throat. Or slapping her across the face. And occasionally while she's tied to a chair. Or all three.
- Tractor Beam
- Western Zodiac: In Space! Organon's astrology. The Doctor, when asked what sign he was born under, replies that he was born under a sign bearing the logo of the Gallifreyan Maternity Service.