Legacy of the Daleks

As the Doctor prepares to search for Sam, he receives a psychic cry of pain and despair from his granddaughter Susan, and discovers that it was focused through another TARDIS on a distant planet. He decides to materialize on Earth following the Dalek invasion, the same time period in which Sam disappeared; perhaps in hope he can find her as well while preventing whatever caused Susan to send the cry.

Following the invasion, Earth is devastatingly underpopulated, and the survivors (in Britain, at least) have coalesced into city-states which are currently engaged in political infighting. Lord Haldoran supplies most of England with power, but Lord London opposes him and many city-states are flocking to London for power supplies. War seems inevitable, but Haldoran has a secret weapon; his mysterious military advisor, Estro, is supplying him with Dalek guns. Meanwhile, Susan and her husband David are having marital difficulties, as it has become increasingly difficult as the decades pass to hide the fact that Susan isn’t aging while David is. Susan is a Peace Officer, one of the elite who keep the Earth safe from the Dalek Artefacts left behind after the invaders were defeated; when she receives word that someone is tampering with the buried DA-17, she sets off to investigate, but is captured by Estro’s men.