Simon Pegg voiced Don Chaney in the Big Finish Doctor Who audio story Invaders from Mars and played the Editor in the Doctor Who television story The Long Game. He also narrated the first series of Doctor Who Confidential.
Pegg wrote and starred in Spaced (alongside Jessica Stevenson), which referenced and parodied many science fiction series, including Doctor Who; the shop in which Pegg's character works has a door that is decorated to resemble the TARDIS. In a DVD commentary, this is noted to have extra significance, for the stockroom on the other side of the door is noticeably larger than the shop floor from which it is seen.
Pegg achieved international attention for his films Shaun of the Dead, in which he starred with Nick Frost, Penelope Wilton and Bill Nighy, Hot Fuzz and Paul. In 2009, Pegg appeared in J.J. Abrams' reinvention of the television franchise Star Trek, carrying on from the late James Doohan in the role of Chief Engineer Montgomery Scott. In doing so he becomes possibly the most famous of only a small number of actors who have appeared in incarnations of both Doctor Who and Star Trek. (Coincidentally, Pegg shares several scenes with another Doctor Who alumnus, Deep Roy, who appears as Scotty's alien assistant.) He also co-wrote the 2016 film, Star Trek Beyond.
In 2012, Pegg provided the voice for the bounty hunter Dengar in the Star Wars: The Clone Wars episode, "Bounty" as well as playing Unkar Plutt in Star Wars: Episode VII The Force Awakens in 2015, making him one of two actors to appear in Star Trek, Star Wars, and Doctor Who, the other being Deep Roy.