Turn Left (Doctor Who) Turn Left (Doctor Who) "Turn Left" is the eleventh episode of the fourth series of British science fiction television series "Doctor Who". It was written by showrunner Russell T Davies and broadcast on BBC One on 21 June 2008. David Tennant only makes a small contribution to this "Doctor-lite" episode as the Tenth Doctor. The story instead focuses on the Doctor's companion, Donna Noble (Catherine Tate) and her encounters with former companion Rose Tyler (Billie Piper). The episode's narrative focuses on an alternative history where the Doctor dies during the events of the 2006 Christmas special "The Runaway Bride". The
Time War (Doctor Who) their demise, the paths between worlds are now closed. The Time Lords could also prevent or repair paradoxes such as the one created by Rose in an attempt to save her father's life in a traffic accident. After the Time Lords' disappearance, such a paradox summons the Reapers, who descended to "sterilise the wound" in time by devouring everything in sight, and are only stopped by Pete Tyler killing himself. Because of the Time Lock, along with the danger of creating a paradox, the Doctor is prevented from going back in time and saving the Time Lords. The Tenth Doctor