This episode goes behind the scenes of The Sontaran Stratagem

Former companion Martha Jones is back and the Earth is under threat from an arch-enemy. From location, there's all the backstage action from the Doctor's latest gripping adventure. As confusion abounds, the Time Lord, Donna and Martha join forces in a battle to save the human race. Featuring interviews with David Tennant, Catherine Tate, Freema Agyeman and Russell T Davies.