Star Wars

Star Wars was a popular science fiction film series.

The Doctor and Frobisher attended the American premiere of the first film at Mann's Chinese Theatre in May 1977. In the 1990s, the series' creator, George Lucas, reedited the first three films and added special effects, a move that was controversial with some fans, though the Doctor claimed to prefer the Special Editions. He also thought actor Peter Cushing (who played Grand Moff Tarkin in the first film, A New Hope) looked familiar. (PDA: Mission: Impractical)

Behind the Scenes
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 * The Doctor's recognition of Peter Cushing was an in-joke referencing the fact that Cushing had played the film version of Dr. Who in the 1960s.
 * Dave Prowse, who had a small role in DW: The Time Monster played the body (though not the voice) of Darth Vader in the first three films.
 * The duel on the Sycorax asteroid in DW: The Christmas Invasion may take some cues the duel between Darth Vader and Luke Skywalker in The Empire Strikes Back. In both scenes, the hero (the Doctor in this case) loses a hand and the weapon held in it. Later, the destruction of the Sycorax asteroid by the Jathaa weaponry is similar to the Death Star's destruction of Alderaan in A New Hope. The Valiant had similar weaponry in DW: The Poison Sky.
 * Star Wars creator George Lucas is an avid fan of the original Doctor Who series.
 * Actor Harrison Ford (Han Solo) was offered the role of the Eighth Doctor in the 1996 Doctor Who television movie but turned it down rather than have a television commitment tie him down. (At the time, the movie's producers hoped to make it the pilot for a re-launched Doctor Who series.)
 * The alien bar scene in The End of Time is very similar to the Mos Eisley Cantina scene in Star Wars Episode IV: A New Hope.
 * The reference in NSA: Forever Autumn to Jar Jar Binks he is in fact a part of the Doctor Who universe, and not just a reference from a film.
 * In a list of teasers for the upcomming episode Victory of the Daleks one of the teasers is Star Wars.