Doppelgänger is a 1969 British science fiction film directed by Robert Parrish and starring Roy Thinnes, Ian Hendry, Lynn Loring and Patrick Wymark. Outside Europe, it is known as Journey to the Far Side of the Sun, which is now the more popular title. In the film, a joint European-NASA mission to investigate a planet in a position parallel to Earth, behind the Sun, ends in disaster with the death of one of the astronauts (Hendry). His colleague (Thinnes) discovers that the planet is a mirror image of Earth.
The first major live-action film of Century 21 writers-producers Gerry and Sylvia Anderson, noted for Thunderbirds and other 1960s "Supermarionation" puppet television series, shooting for Doppelgänger ran from July to October 1968. Using Pinewood Studios as the principal production base, Parrish also filmed on location in both England and Portugal. The professional relationship between the Andersons and their director became strained as the shooting progressed, while creative disagreements with cinematographer John Read resulted in his resignation from Century 21.
Doppelgänger premiered in August 1969 in the United States and October of that year in the United Kingdom. Although the film in general has been praised for the quality of its special effects and set design, the plot device of the parallel Earth has attracted criticism, with some commentators judging it to be clichéd and uninspired in comparison to the precedent established by earlier science fiction. In addition, although Doppelgänger has frequently been interpreted as a pastiche of major science-fiction films of the 1960s, including 2001: A Space Odyssey (1968), some of the devices and imagery used have been dismissed as weak imitations of the originals. Since release, it has been termed a cult film.
Actors and props from Doppelgänger would re-appear in a later Anderson TV series, UFO. Although the Andersons incorporated adult themes into their script in an effort to distinguish the film from their children's TV productions, cuts to more mature content, in this case a shot of a pack of contraceptive pills, were required to permit an A and, later, PG certificate from the BBFC.