While searching for his lost companion, Sam, the Doctor finds himself, in Domain London. But it seems that Susan is now missing too, and his efforts to find her lead to confrontation with the ambitious Lord Haldoran, who is poised to take control of southern England through all-out war. With the help of a sinister adviser, Haldoran's plans are already well advanced. Power cables have been fed down a mineshaft, reactivating a mysterious old device of hideous power. But has the Dalek presence on Earth really been wiped out? Or are there still traps for the unwary?
The Doctor learns to his cost once again when dealing with the evil of the Daleks, nothing can be taken at face value...