Following the events of Longest Day, Sam is trapped on the Kusk ship with no food and no way to control where the ship goes. She is rescued by a ship headed to a mining colony, and befriends a tentacled alien named Alloise. Alloise is on the way to the Dreamstone mines to protest corporate offenses against the local life.
The Doctor, having just finished fighting the Daleks on Earth, manages to track the ship that picked up Sam and also shows up on the Dreamstone Moon, but gets sidetracked (as the Eighth Doctor often does) investigating the death of a miner.
There's something sinister going on on the Dreamstone Moon. As attacks on miners and other staff increase, the anti-alien Earth military shows up to try to handle the situation. It soon becomes clear that the alien they are fighting can induce hallucinations, causing all the more confusion. Only one thing is certain: something is living in the Dreamstone, and it wants to kill them.
Tropes present in Dreamstone Moon include:
- Catfolk: The Besiddians, including Anton's girlfriend. They have five rows of teeth but are otherwise typical catpeople. The males are twice as big and half as smart as the females.
- Dangerous Workplace: When you're mining sentient rocks that want to kill you (though they don't know that yet), it can get a bit dangerous.
- Dreaming of Things to Come: Anton. That's why he goes to the Dreamstone Moon in the first place.
- Dream Weaver: Anton La Serre. He's one of the old-fashioned ones, so he hates this new Dreamstone product that's shown up recently.
- Genius Loci: The Dreamstone Moon (and the planet below).
- Missed Him by That Much: Although the Doctor arrives in the Mu Camelopides system specifically to pick up Sam, events conspire so they're never quite in the same place at the same time. On the one occasion they do see each other, they're on opposite sides of a crowded room.
- Sliding Scale of Anthropomorphism: There's quite a decent diversity of aliens. Everything from humans to vaguely humanoid aliens to tentacled and spider-like aliens
- Space Whale Aesop: Don't use environmentally unfriendly mining techniques because the rocks might be sentient and try to kill you.
- Talking the Monster to Death: The Doctor comments on the implications at the end.After a while, the Doctor realised that he'd just killed a man with the force of an argument.
It wasn't a very pleasant thought.