When the first two Doctors are kidnapped from time and space, his future selves are contacted by a voice claiming to be the President of the Time Lords. He sends them on a quest to rescue the Doctors' two missing incarnations.
The Doctors arrive in Medieval Wales, just as a fleet of battle-hungry Sontarans attack Cardiff Castle. The ensuing battle leaves nine incarnations of the Doctor for dead.
On the planet Raston the Doctors arrive at the heart of the Dalek-Cyber War. In the aftermath of battle they discover an invisible barrier which hides a dark and sinister secret.
Bluffs and double-bluffs abound as the Doctors try to outwit their ultimate foe. But not every day is a victory and the Doctors have already lost far more than they ever realised. Can they now save themselves from oblivion?