The Doctor and Paterson manage to escape from the Master and join up with Ace and her friends, where the Doctor tries to find a way to get them all off the planet before it explodes.
Perivale, England, the late 1980s. People are vanishing into thin air under the baleful stare of a very strange cat. The Doctor and Ace learn that, in the battle for survival, success can carry a terrible price...
Fenric is loose and planning to use the Ancient Haemovore to poison the Earth with chemicals, unless the Doctor can defeat him in their centuries old game.
England, the 1940s. The TARDIS brings the Doctor and Ace to a secret naval base during WWII. There, the time-travellers battle vampiric Haemovores and an ancient Viking curse!
Only Redvers, still searching for the elusive Saxe-Coburg, seems able to withstand Light and communicate with Control. Ace realises her past actions need to be dealt with.
The Doctor and Ace explore Victorian house Gabriel Chase and realise it hides just as many dark secrets in its drawing room as it does in its dark cellar.
Morgaine forces Ace and Shou Yuing to hand over Excalibur by threatening to release the Destroyer, so the Doctor and the Brigadier enter a dimensional portal to stop her.
As UNIT are transporting a nuclear warhead around Carbury, knights in armour arrive to continue waging a war that began thousands of years ago, but in a wholly different dimension.