The Doctor meet Professor Parry and his archaeologists on the planet Telos. The expedition is there to unearth the remains of Cybermen who died out long ago. Or did they?
The Doctor and Romana are swept up in the political machinations of Tara. The Doctor must keep the android "king" running while Grendel plots to use Romana to destroy him.
The Doctor must employ a desperate gambit to keep the evil Grendel off the throne, and the Count has a new pawn to play - Romana.
Grendel plans two weddings and a funeral to cement his hold over Tara. The Doctor and K-9 race to foil him and save the Time Lady's life.
Mike Yates (who left UNIT after his involvement in the affair with the Dinosaurs) contacts Sarah-Jane about mysterious goings on in a Buddhist retreat in the English countryside. Soon it becomes apparent that an extraterrestrial force is attempting to reclaim a crystal the Doctor 'borrowed' from Metebelis 3.