The Doctor and Ace travel back to London in November 1963 and are caught in the middle of a Dalek civil war.

With two factions of Daleks involved in a race war on Earth, the Doctor takes care of old business by having the Hand of Omega ceremoniously but quietly buried in a churchyard. His actions do not go unobserved, and leaving behind a bored Ace without a purposeful outlet could spell trouble as well.

The Doctor plans to let one of the Dalek factions have the Hand of Omega (but not too easily, of course) while keeping Gilmore and his military men preoccupied in a safe territory, but that plan could be threatened by a mole in their midst and a miscalculation on the Doctor's part.

The Imperial Dalek Emperor reveals himself to be an old, familiar adversary of the Doctor. Now with the Hand of Omega, the Imperial Daleks expect to rule over both Time and the Time Lords. The only snag in the Doctor's plan to thwart this may come from the fascist mole in Gilmore's unit - discovered and detained but escaped to cause mischief, putting both Ace's life a...

The Doctor and Ace arrive on the earth colony of Terra Alpha, a colony that is under the misguided dictatorship of Helen A. On Terra Alpha, sadness and misery are capital crimes, and "killjoys' (anyone who does not adhere to these strict laws) are executed on the spot by Helen A's secret police, a motley crew of female assassins known only as "The Happiness Patrol".

The Doctor and Earl manage to escape from the Kandy Man and join up with the planet's natives, the Pipe People, enlisting their help to rescue Ace.

Helen A has sentenced Ace and Susan Q to the last show at the forum but the Doctor has a plan to rescue them and topple Helen A's regime.

Earth faces imminent destruction. Nemesis, a comet containing a statue composed of Validium (living metal) is due to strike, needing only its bow and arrow to achieve critical mass and become active. Four converging parties know of its power: the Doctor, neo-Nazi assault troops from South America, a 17th-century noblewoman steeped in the black arts (in whose image the...

As hostilities break out between factions vying for ownership of the comet, the Doctor goes after the worst of the lot - Cybermen, using Ace's upgraded boom box to flood Cyber Communications with jazz music while trying to locate the whereabouts of the fleet beyond this mere scouting party.

With the Cyber Fleet poised nearby, the Doctor may have no choice but to let them have Nemesis. Meanwhile, Lady Peinforte and Richard navigate modern society, De Flores encounters an open betrayal, and Ace combats Cybermen with a slingshot.

The Doctor persuades Ace to visit the Psychic Circus on the planet Segonax despite her fear of clowns.

The Doctor and Ace reach the Psychic Circus, where the Doctor is imprisoned with the other contestants while Ace draws the attention of the Chief Clown.

Mags helps the Doctor escape and Deadbeat leads him to Ace, where Bellboy tells them what happened to the Psychic Circus.

The Doctor goes into the Dark Circus and defeats the Gods Of Ragnarok, helped by Ace, Kingpin and Mags. Captain Cook, the clowns and the Chief Clown are killed. The circuses are destroyed.