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
Doctor Who Following the success of the 2005 series produced by Russell T Davies, the BBC commissioned Davies to produce a 13-part spin-off series titled "Torchwood" (an anagram of "Doctor Who"), set in modern-day Cardiff and investigating alien activities and crime. The series debuted on BBC Three on 22 October 2006. John Barrowman reprised his role of Jack Harkness from the 2005 series of "Doctor Who". Two other actresses who appeared in Doctor Who also star in the series; Eve Myles as Gwen Cooper, who also played the similarly named servant girl Gwyneth in the 2005 "Doctor Who" episode "The Unquiet Dead",