The Sontarans activate their masterplan and begin to choke the whole of planet Earth, as Russell T Davies's Bafta Award-winning time-travelling drama continues. UNIT is left defenceless, with a traitor in their ranks. And as interplanetary war edges closer, the Doctor has to fight to keep both Martha and Donna alive – but will he have to make the ultimate sacrifice?
David Tennant plays the Doctor and Catherine Tate plays his companion, Donna Noble. Freema Agyeman and Christopher Ryan guest star.
Streaming Options