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
Doomsday (Doctor Who) filmed between November 2005 and January 2006, alongside the episodes "Rise of the Cybermen" and "The Age of Steel". Set mainly in the One Canada Square skyscraper in Canary Wharf, the episode's plot consists mostly of the Daleks and Cybermen waging a global war, with humanity on the verge of extinction in the cataclysm. The Tenth Doctor (David Tennant), the Tyler family, and Mickey Smith fight for their lives trying to reverse the situation. They are successful, but at an emotional cost to the Doctor and Rose, as they are left in separate universes. The episode is one of the