Doctor Who (2013 specials) Doctor", saw the departure of Smith from the series and the introduction of Peter Capaldi as the Twelfth Doctor. "The Day of the Doctor" features the return of the Zygons for the first time since "Terror of the Zygons" in 1975. "The Time of the Doctor" draws together a number of plot threads that have run through the series since the Eleventh Doctor's first episode in 2010. <onlyinclude></onlyinclude> In "The Day of the Doctor", Smith and Coleman star alongside David Tennant and Billie Piper; Tennant reprised his role as the Tenth Doctor, while Piper, although credited as playing Rose Tyler,
Doomsday (Doctor Who) the alternate universe Pete Tyler, who tells him that after he left the Cybermen were sealed in their factories while humanity decided what to do with them. In the meantime, the Cybermen vanished and the breach began causing unprecedented global warming on the parallel Earth, which the Doctor theorises is the start of the process that will lead to both planets falling into the Void. Pete demands the Doctor seal the breach before his Earth is destroyed. Meanwhile, Rose deduces that she and Mickey were kept alive because their touch can activate the Genesis Ark. Dalek Sec explains that they