Doctor Who is a British science fiction television programme produced by the BBC. The programme depicts the adventures of a mysterious alien time-traveller known as "the Doctor" who travels in his space and time-ship, the TARDIS, which appears from the exterior to be a blue 1950s police box. With his companions, he explores time and space, solving problems, facing monsters and righting wrongs. The programme is listed in Guinness World Records as the longest-running science fiction television show in the world and is also a significant part of British popular culture. It has been recognised for its imaginative stories, creative low-budget special effects during its original run, and pioneering use of electronic music (originally produced by the BBC Radiophonic Workshop). In the United Kingdom and elsewhere, the show has become a cult television favourite and has influenced generations of British television professionals, many of whom grew up watching the series. It has received recognition from critics and the public as one of the finest British television programmes, including the BAFTA Award for Best Drama Series in 2006. The programme originally ran from 1963 to 1989. After an unsuccessful attempt to revive regular production with a backdoor pilot in the form of a 1996 television film, the programme was successfully relaunched in 2005, produced in-house by BBC Wales in Cardiff. Some development money for the new series is contributed by the Canadian Broadcasting Corporation (CBC), which is credited as a co-producer. Doctor Who has also spawned spin-offs in multiple media, including the current television programmes Torchwood and The Sarah Jane Adventures, and the 1981 pilot episode K-9 and Company. The show's lead character is currently portrayed by David Tennant. In the programme's most recent series, which ran from 5 April to 5 July 2008, Catherine Tate played the Doctor's companion, reprising her role of Donna Noble from the 2006 Christmas special. Another Christmas special will air in 2008, followed by four more specials in 2009; the next full series has been confirmed for airing in 2010.

Doctor Who first appeared on BBC television at 5:15 pm (GMT) on 23 November 1963,[8] following discussions and plans that had been in progress for a year. The Head of Drama, Sydney Newman, was mainly responsible for developing it, with the first format document for the series being written by Newman along with the Head of the Script Department (later Head of Serials) Donald Wilson and staff writer C. E. Webber. Writer Anthony Coburn, story editor David Whitaker and initial producer Verity Lambert also heavily contributed to the development of the series. The series' title theme was composed by Ron Grainer and realised by Delia Derbyshire of the BBC Radiophonic Workshop. The programme was originally intended to appeal to a family audience. The BBC drama department's Serials division produced the programme for 26 series, broadcast on BBC One. Viewing numbers that had fallen (though comparably increased at some points), a decline in the public perception of the show and a less prominent transmission slot saw production suspended in 1989 by Jonathan Powell, Controller of BBC One. Although it was effectively cancelled (as series co-star Sophie Aldred reported in the documentary Doctor Who: More Than 30 Years in the TARDIS), the BBC said the series would return. While in-house production had ceased, the BBC was hopeful of finding an independent production company to relaunch the show. Philip Segal, a British expatriate who worked for Columbia Pictures' television arm in the United States, approached the BBC about such a venture. Segal's negotiations eventually led to a television movie. The Doctor Who television movie was broadcast on the Fox Network in 1996 as a co-production between Fox, Universal Pictures, the BBC, and BBC Worldwide. Although the film was successful in the UK (with 9.1 million viewers), it was less so in the United States and did not lead to a series. Licensed media such as novels and audio plays provided new stories, but as a television programme Doctor Who remained dormant until 2003. In September of that year, BBC Television announced the in-house production of a new series after several years of unsuccessful attempts by BBC Worldwide to find backing for a feature film version. The executive producers of the new incarnation of the series are writer Russell T Davies and BBC Wales Head of Drama/BBC Television Controller of Drama Commissioning Julie Gardner. It has been sold to many other countries worldwide (see Viewership). Doctor Who finally returned with the episode "Rose" on BBC One on 26 March 2005. There have been three further series in 2006, 2007, and 2008 and Christmas Day specials in 2005, 2006 and 2007. The fourth series began on BBC One on 5 April 2008. There will be a rest year in 2009, with no new series, although David Tennant will star in 4 specials in that year. After the 2008 Christmas special and four special episodes in 2009, a fifth full-length series is planned for Spring 2010, with Steven Moffat replacing Davies as head writer and executive producer. The 2005–present version of Doctor Who is considered a direct continuation of the 1963–89 series, as is the 1996 telefilm. This differs from other series relaunches that have either been reimaginings or reboots (e.g., Battlestar Galactica and Bionic Woman) or series taking place in the same universe as the original but with a totally new cast of characters (e.g., Star Trek: The Next Generation and spin-offs).

Doctor Who originally ran for 26 seasons on BBC One, from 23 November 1963 until 6 December 1989. During the original run, each weekly episode formed part of a story (or "serial") — usually of four to six parts in earlier years and three to four in later years. Notable exceptions were the epic The Daleks' Master Plan, which aired in twelve episodes (plus an earlier one-episode teaser, "Mission to the Unknown", featuring none of the regular cast), almost an entire season of 7-episode serials (season 7), the 10-episode serial The War Games, and The Trial of a Time Lord, which ran for 14 episodes (albeit divided into three production codes and four narrative segments) during Season 23. Occasionally serials were loosely connected by a storyline, such as Season 16's quest for The Key to Time or Season 18's journey through E-Space and the theme of entropy. The programme was intended to be educational and for family viewing on the early Saturday evening schedule. Initially, it alternated stories set in the past, which would teach younger audience members about history, with stories set either in the future or in outer space to teach them about science. This was also reflected in the Doctor's original companions, one of whom was a science teacher and another a history teacher. However, science fiction stories came to dominate the programme and the "historicals", which were not popular with the production team, were dropped after The Highlanders (1967). While the show continued to use historical settings, they were generally used as a backdrop for science fiction tales, with one exception: Black Orchid set in 1920s UK. The early stories were more serial-like in nature, with the narrative of one story flowing into the next, and each episode having its own title, although produced as distinct stories with their own production codes. Following The Gunfighters (1966), however, each serial was given its own title, with the individual parts simply being assigned episode numbers. What to name these earlier stories is often a subject of fan debate. Writers during the original run included Terry Nation, Henry Lincoln, Douglas Adams, Robert Holmes, Terrance Dicks, Dennis Spooner, Eric Saward, Malcolm Hulke, Christopher H. Bidmead, Stephen Gallagher, Brian Hayles, Robert Sloman, Chris Boucher, Peter Grimwade, Marc Platt and Ben Aaronovitch. The serial format changed for the 2005 revival, with each series consisting of thirteen 45-minute, self-contained episodes (60 minutes, with adverts, on overseas commercial channels), and an extended episode broadcast on Christmas Day. Each series includes several standalone and multi-part stories, linked with a loose story arc that resolves in the series finale. As in the early "classic" era, each episode — whether standalone or part of a larger story — has its own title. 751 Doctor Who instalments have been televised since 1963, ranging from 25-minute episodes (the most common format), to 45-minute episodes (for Resurrection of the Daleks in the 1984 series, a single season in 1985, and the revival), to two feature-length productions (1983's "The Five Doctors" and the 1996 television movie), to the two 60-minute Christmas specials produced for the revival and the more recent 72 minute 2007 Christmas Special. The current series is recorded in 576i25 DigiBeta wide-screen format and then filmised to give a 25p image in post-production using a Snell & Wilcox Alchemist Platinum.

Between about 1964 and 1974, large amounts of older material stored in the BBC's various video tape and film libraries were either destroyed or simply wiped. This included many old episodes of Doctor Who, mostly stories featuring the first three Doctors — William Hartnell, Patrick Troughton and Jon Pertwee. Following consolidations and recoveries the archives are complete from the programme's move to colour television (starting from Jon Pertwee's time as the Doctor), although a few Pertwee episodes have required substantial restoration; a handful have been recovered only as black and white films, and several survive in colour only as NTSC copies recovered from North America (a few of which are domestic, off-air Betamax tape recordings, not transmission quality). In all, 108 of 253 episodes produced during the first six years of the programme are not held in the BBC's archives. It has been reported that in 1972 almost all episodes then made were known to exist at the BBC, whilst by 1978 the practice of wiping tapes had ended. Some episodes have been returned to the BBC from the archives of other countries who bought copies for broadcast, or by private individuals who got them by various means. Early colour videotape recordings made off-air by fans have also been retrieved, as well as excerpts filmed from the television screen onto 8 mm cine film and clips that were shown on other programmes. Audio versions of all of the lost episodes exist from home viewers who made tape recordings of the show. In addition to these, there are off-screen photographs made by photographer John Cura, who was hired by various production personnel to document many of their programmes during the 1950s and 1960s, including Doctor Who. These have been used in fan reconstructions of the serials. These amateur reconstructions have been tolerated by the BBC, provided they are not sold for profit and are distributed as low quality VHS copies. One of the most sought-after lost episodes is Part Four of the last William Hartnell serial, The Tenth Planet (1966), which ends with the First Doctor transforming into the Second. The only portion of this in existence, barring a few poor quality silent 8 mm clips, is the few seconds of the regeneration scene, as it was shown on the children's magazine show Blue Peter. With the approval of the BBC, efforts are now under way to restore as many of the episodes as possible from the extant material. Starting in the early 1990s, the BBC began to release audio recordings of missing serials on cassette and compact disc, with linking narration provided by former series actors. "Official" reconstructions have also been released by the BBC on VHS, on MP3 CD-ROM and as a special feature on a DVD. The BBC, in conjunction with animation studio Cosgrove Hall has reconstructed the missing Episodes 1 and 4 of The Invasion (1968) in animated form, using remastered audio tracks and the comprehensive stage notes for the original filming, for the serial's DVD release in November 2006. Although no similar reconstructions have been announced as of early 2007, Cosgrove Hall has expressed an interest in animating more lost episodes in the future, despite the announcement in April 2007 that this project is on indefinite hiatus. In April 2006, Blue Peter launched a challenge to find these missing episodes with the promise of a full scale Dalek model.

The character of the Doctor was initially shrouded in mystery. All that was known about him in the programme's early days was that he was an eccentric alien traveller of great intelligence who battled injustice while exploring time and space in an unreliable old time machine called the TARDIS, an acronym for Time And Relative Dimension(s) In Space. As it appears much larger on the inside than on the outside, the TARDIS has been described by the Third Doctor as "dimensionally transcendental" and, due to a malfunction of its Chameleon Circuit, is stuck in the shape of a 1950s-style British police box. However, not only did the initially irascible and slightly sinister Doctor quickly mellow into a more compassionate figure, it was eventually revealed that he had been on the run from his own people, the Time Lords of the planet Gallifrey. As a Time Lord, the Doctor has the ability to regenerate his body when near death. Introduced into the storyline as a way of continuing the series when the writers were faced with the departure of lead actor William Hartnell in 1966, it has continued to be a major element of the series, allowing for the recasting of the lead actor when the need arises. The serial The Deadly Assassin established that a Time Lord can regenerate twelve times, for a total of thirteen incarnations (although at least one Time Lord, The Master, has managed to circumvent this). To date, the Doctor has gone through this process and its resulting after-effects on nine occasions, with each of his incarnations having his own quirks and abilities but otherwise sharing the memories and experience of the previous incarnations:

First Doctor, played by William Hartnell (1963–1966)

Second Doctor, played by Patrick Troughton (1966–1969)

Third Doctor, played by Jon Pertwee (1970–1974)

Fourth Doctor, played by Tom Baker (1974–1981)

Fifth Doctor, played by Peter Davison (1981–1984)

Sixth Doctor, played by Colin Baker (1984–1986)

Seventh Doctor, played by Sylvester McCoy (1987–1989, 1996)

Eighth Doctor, played by Paul McGann (1996)

Ninth Doctor, played by Christopher Eccleston (2005)

Tenth Doctor, played by David Tennant (2005–) 

Other actors have also played the Doctor, though rarely more than once (see the list of actors who have played the Doctor). Despite these shifts in personality, the Doctor remains an intensely curious and highly moral adventurer who would rather solve problems with his wits than by using violence. Throughout the programme's long history there have been controversial revelations about the Doctor. For example, in The Brain of Morbius (1976), it was hinted that the First Doctor may not have been the Doctor's first incarnation (although the other faces depicted may have been incarnations of the Time Lord Morbius); during the Seventh Doctor's era it was hinted that the Doctor was more than just an ordinary Time Lord. In the Eighth Doctor movie, the Doctor described himself as being "half human". The revelation has become controversial amongst series fans, given that there have been no references to the concept during the original or revived television series. The very first episode, An Unearthly Child, revealed that the Doctor has a granddaughter, Susan Foreman, and in "Fear Her" (2006), he remarked that he had, in the past, been a father. The 2005 series revealed that the Ninth Doctor thought he had become the last surviving Time Lord, and that his home planet had been destroyed. In the 2008 series episode "The Doctor's Daughter", the Doctor's cells are used to produce a daughter (played by Georgia Moffett, the real-life daughter of Fifth Doctor actor Peter Davison) who is subsequently named Jenny by Donna as a result of the Doctor describing her as "a generated anomaly".

COMPANIONS:

The Doctor almost always shares his adventures with up to three companions, and since 1963 more than 35 actors and actresses have featured in these roles. The First Doctor's original companions were his granddaughter Susan Foreman (Carole Ann Ford) and school teachers Barbara Wright (Jacqueline Hill) and Ian Chesterton (William Russell). The only story from the original series in which the Doctor travels alone is The Deadly Assassin. Dramatically, the companion characters provide a surrogate with whom the audience can identify, and serve to further the story by requesting exposition from the Doctor and manufacturing peril for the Doctor to resolve. The Doctor regularly gains new companions and loses old ones; sometimes they return home or find new causes — or loves — on worlds they have visited. Some have even died during the course of the series. Although the majority of the Doctor's companions have been young, attractive females, the production team for the 1963–1989 series maintained a long-standing taboo against any overt romantic involvement in the TARDIS. The taboo was controversially broken in the 1996 television film when the Eighth Doctor was shown kissing companion Grace Holloway. The 2005 series played with this idea by having various characters think that the Ninth Doctor and Rose (played by Billie Piper) were a couple, which they vehemently denied (see also "The Doctor and romance"). The idea of a possible involvement was suggested again in "Smith and Jones", when the Tenth Doctor kisses his soon-to-be new companion Martha Jones, although the Doctor insists that the kiss was simply for the purpose of 'genetic transfer'. In "The Unicorn and the Wasp", the Doctor is kissed by Donna Noble to shock him in order to neutralise a poison in his system. Previous companions reappeared in the series, usually for anniversary specials. One former companion, Sarah Jane Smith (played by Elisabeth Sladen), together with the robotic dog K-9, appeared in an episode of the 2006 series more than twenty years after their last appearances in the 20th Anniversary story "The Five Doctors" (1983). Afterwards, the character was featured in the spinoff series The Sarah Jane Adventures. Sladen once again appeared as Sarah Jane in the final two episodes of the fourth season of the new Doctor Who, with K-9 appearing briefly in the final episode, "Journey's End". The latest companions of the Doctor included a large ensemble cast ranging from Catherine Tate reprising her role as Donna, Billie Piper as Rose, Noel Clarke as Mickey Smith, Freema Agyeman as Martha, Elisabeth Sladen as Sarah Jane and John Barrowman as Captain Jack, all of whom departed in the episode "Journey's End". Agyeman appeared as Martha Jones in three episodes of the spin-off series Torchwood before returning to Doctor Who halfway through the fourth series. Billie Piper briefly reprised her role as Rose Tyler in the fourth series episode "Partners in Crime" and returned to the series from "Turn Left" to "Journey's End". For the 2007 Christmas episode "Voyage of the Damned", the Doctor's companion was Astrid Peth, played by Australian performer Kylie Minogue. Though arguably not a companion, Brigadier Lethbridge-Stewart was a recurring character in the original series making his first appearance alongside the Second Doctor and his final alongside the Seventh. The actor Nicholas Courtney who portrayed the Brigadier had previously also starred as Bret Vyon alongside first Doctor William Hartnell in the 12-part The Daleks' Master Plan, and he has appeared with every doctor of the classic series except Colin Baker, although he appears with the Sixth Doctor in the charity crossover special Dimensions in Time. His photo appears among Sarah Jane Smith's personal items in The Sarah Jane Adventures. He and UNIT appeared regularly during the Third Doctor's tenure, and it has continued to appear or be referred to in the revival of the show and its spin-offs.

ENEMIES:

When Sydney Newman commissioned the series, he specifically did not want to perpetuate the cliché of the "bug-eyed monster" of science fiction. However, monsters were a staple of Doctor Who almost from the beginning and were popular with audiences. Notable adversaries of the Doctor from the series' initial 26-year run include the Autons, the Cybermen, the Sontarans, the Zygons, the Sea Devils, the Silurians, the Ice Warriors, the Rani, the Yeti, Davros (the creator of the Daleks), the Master (a Time Lord with a thirst for universal conquest), and, most notably, the Daleks. This continued with the resurrection of the series in 2005. Current executive producer, Russell T Davies, stated that it had always been his intention to bring back classic icons of Doctor Who one step at a time: Daleks in series 1, Cybermen in series 2 and the Master in series 3. He also stated that he was not finished and would continue reviving villains from the series' past. Series 4 saw the return of the Sontarans and the Daleks' creator, Davros. Since its 2005 return, the series has also introduced new aliens, including the Slitheen, the Ood and the Judoon.

DALEKS:

Of all the monsters and villains, the ones that have most secured the series' place in the public's imagination are the Daleks, who first appeared in 1963 and were the series' very first "monster". The Daleks are Kaled mutants in tank-like mechanical armour shells from the planet Skaro. Their chief role in the great scheme of things, as they frequently remark in their instantly recognisable metallic voices, is to "Exterminate!" all beings inferior to themselves, even destroying the Time Lords in the often referenced but never shown Time War. Davros, the Daleks' creator, became a recurring villain after he was introduced in Genesis of the Daleks, in which the Time Lords send the Doctor back to either destroy the Daleks, avert their creation, or tamper with their genetic structure to make them less warlike. Davros has been played by Michael Wisher (first introduced in Genesis of the Daleks), David Gooderson (Destiny of the Daleks), and Terry Molloy. Davros returned to Doctor Who portrayed by Julian Bleach in the 2008 episodes "The Stolen Earth" and "Journey's End". The Daleks were created by writer Terry Nation (who intended them as an allegory of the Nazis) and BBC designer Raymond Cusick. The Daleks' début in the programme's second serial, The Daleks (1963–64), caused a tremendous reaction in the viewing figures and the public, putting Doctor Who on the cultural map. A Dalek appeared on a postage stamp celebrating British popular culture in 1999, photographed by Lord Snowdon.

CYBERMEN:

Cybermen were originally a wholly organic species of humanoids originating on Earth's twin planet Mondas that began to implant more and more artificial parts into their bodies. This led to the race becoming coldly logical and calculating, with emotions usually only shown when naked aggression was called for. The 2006 series introduced a totally new variation of Cybermen created in a parallel universe.

THE MASTER:

The Master is a renegade Time Lord, and the Doctor's nemesis. Conceived as "Professor Moriarty to the Doctor's Sherlock Holmes," the character first appeared in 1971. As with the Doctor, the role has been portrayed by several actors, the first being Roger Delgado who continued in the role until his death in 1973. The Master was briefly played by Peter Pratt and Geoffrey Beevers until Anthony Ainley took over and continued to play the character until Doctor Who's "hiatus" in 1989. The Master returned in the 1996 television movie of Doctor Who, played by Gordon Tipple in the ultimately unused pre-credits voiceover, then Eric Roberts, and in the three-part finale of the 2007 series, portrayed by Derek Jacobi, who then regenerated into John Simm at the conclusion of the episode "Utopia".