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
Midnight (Doctor Who) Doctor tells her, "Molto bene", in relief. Donna copies him. Disturbed, the Doctor tells Donna not to do that, then looks away. Dee Dee tells the Doctor that she has written a paper on the lost moon of Poosh. The Doctor also mentions the Medusa Cascade, and Rose Tyler appears briefly on a television screen. These are all references to the series 4 story arc. Rose appears along with the missing planets, including Poosh, in the two-part season finale "The Stolen Earth"/"Journey's End". This episode is the fiftieth episode filmed for the revived series, and was filmed at the same