The end is nigh! Nostradamus foresees it! Ships are coming, and fire threatens to engulf the world. But he did not see the strange man in his "TARDIS" in his dreams, but it's too late.
The Doctor will watch the world burn, and help in its destruction.
The Doomsday Quatrain contains examples of the following tropes:
- Apple of Discord: The Doctor starts this in the Kro Phalanx.
- Bavarian Fire Drill:There traitor! Chaaaase traaitooor!
- But Thou Must!: The Doctor wants to go to Celdor, but the TARDIS repeatedly plonks him down in Florence in the sixteenth century. note
- Call-Back: The Doctor says Nostradamus' wife once knitted him quite a fancy scarf.
- Call-Forward: The Doctor says he knows when the world will end.
- Computer Voice
- Disney Villain Death: Brors.
- Dreaming of Things to Come: How Nostradamus sees the future.
- Eaten Alive: Poor, poor Larret.
- Enemy Civil War: What the Apple of Discord eventually, with a lot of Conflict Ball, evolves into.
- Fantastic Nature Reserve: The Poldegons recreate planets to sell off for destruction inside of their station. When the Doctor is first introduced to this concept he sees an ocean.
- Fantastic Racism: The Doctor mentions the Kro discriminate between long snouts and short tails. Sure enough later a Kro shouts "Short-tailed INCOMPETENT" at another Kro.
- Faux Affably Evil: Administrator Brors.
- First-Name Basis: Despite the fact the name Nostradamus is very well known, in story he keeps getting called by his first name, Michel.
- Genetic Memory: The Kro can eat the brains of their kin, and gain their memories.
- Green-Skinned Space Babe: The Poldegons are blue though.
- Have We Met Yet?: The Doctor will, in his own personal future, meet a previous Kro brood.
- Historical Domain Character: Nostradamus.
- Holographic Disguise: The Poldegons use these to appear human.
- Insistent Terminology: "Bio-Units". Not "Humans".
- Just Following Orders: One of the soldiers taking away Nostradamus barks this at the Doctor, and the Doctor muses he encounters far too many of those throughout his journeys.
- Lizard Folk: The Kro.
- Mythology Gag: The Doctor gets asked if the symbols on his tunic were the signs of his estate. The question marks have been a Doctor Who staple starting with Tom Baker's burgundy outfit, up until Sylvester McCoy's outfit pre-The Movie.
- The Nth Doctor: The Kro call the Doctor "The Doctor of Seventh".
- Planet Looters: The Kro bought the rights to attack Earth for training purposes of their warriors from the Poldegons.
- Seers: Nostradamus, as he is notoriously referred to in history.
- Sequel Hook / The Unreveal: Garilund gives the Doctor a prophecy Nostradamus had about the Doctor and that he could change it. We're left with:The Doctor: Oh well.Garilund: What does it mean, Doctor?The Doctor: That's what I'm going to find out!
- Villainous Breakdown: Brors turns into a full fledged madman towards the end, trying to kill Kren and Garilund because they betrayed him, even going so far as to go into a collapsing realm to kill them. If he'd done nothing, they more than likely simply would have perished.
