Doctor Who (series 4) Astrid Peth, who died during the events of the episode. The companions in the regular series had all been in the lead companion role previously: the primary role of Donna Noble, who was introduced in "The Runaway Bride", was played by Catherine Tate for all thirteen episodes. Her return was announced by the BBC on 3 July 2007. Freema Agyeman, who portrayed the Doctor's companion Martha Jones in series three, returned for "The Sontaran Stratagem", "The Poison Sky", "The Doctor's Daughter", "The Stolen Earth" and "Journey's End". Billie Piper, who played Rose Tyler from the first episode of the new
Rose (Doctor Who episode) the head to locate the controlling signal. With the head connected, the TARDIS takes them to the London Eye. The Doctor explains to Rose that the fake Mickey was an Auton, controlled by a signal from the Nestene Consciousness. He has a vial of anti-plastic that can be used to destroy the Nestene if necessary. Realising that the transmitter is the London Eye itself, Rose and the Doctor descend underneath it to stop the Nestene Consciousness. They find Mickey, tied up but alive, and the Doctor speaks to the Nestene Consciousness. He tries to negotiate with it, but the Consciousness