Doctor Who is a BBC science fiction television series. The series is about an alien time-traveller known as "the Doctor". In her space-time ship, the TARDIS (Time and Relative Dimension in Space), the Doctor and her companions travel through space and time.

The television series ran from 1963–1989 and started running again in 2005. It is the longest running science fiction television series in the world.

There were two Doctor Who movies made in the 1960s. Peter Cushing played the Doctor in these movies, but he was not the Doctor in the television series. In 1996, there was also a television movie starring Paul McGann. There have been many other versions of Doctor Who in books, comics, games, other shows, music videos, remixes, fan fiction, documentaries, the news, in magazines, toys, cosplay, decorations, on the internet, on radios, on DVDs, on Bluray, On other disc formats and other forms of entertainment.

Story outline 
The story is about a person who calls themselves "The Doctor". They travel in their space-time-ship TARDIS ("Time And Relative Dimension In Space"), with which he can go anywhere in time and space. Because of an error in its chameleon circuit, the outside of the TARDIS always looks like a 1960s-style British police public call box (similar to a blue telephone box), but on the inside the TARDIS is much bigger.

The Doctor is an alien, a Time Lord from the planet Gallifrey. At first, they travelled only with their granddaughter Susan Foreman. Later, the Doctor took other people with them. They are usually called "companions" or "assistants". The Doctor and their companions travel through space and time, have a lot of adventures, and often save many people.

Some people think that the Doctor's name is not actually "Doctor Who", but other people think there is no mistake. The character was named Doctor Who in the titles until the Fifth Doctor, and after the 2005 restart the Ninth Doctor, played by Christopher Eccleston, is called Doctor Who in the titles too. The Second Doctor once signed a letter as "Dr W.".

History 
Doctor Who was first shown in 1963, with William Hartnell as the Doctor. When Hartnell left the show in 1966, the writers came up with the idea that the Doctor would regenerate (at the time called renewal) and transform into the Second Doctor, who was played by Patrick Troughton. In 1970, when Jon Pertwee took over as the Third Doctor, the series switched from black-and-white to colour.

Before 1978, the BBC would sometimes throw away episodes they did not need. This was because they did not usually show episodes on television more than once, and they needed to reuse video tape to record new broadcasts. Some of the episodes that were thrown away have been found since then, but 97 of the 851 episodes are still missing. However, audio recordings of all missing episodes exist, and some of these have been released on home video with animations.

Seven actors played the Doctor from 1963 until 1989, when the series stopped. In 1996, the BBC teamed with Fox Broadcasting Company and Universal Pictures to create a film version, in which Paul McGann played the Eighth Doctor. It was hoped that the film would lead to a new series, but this did not happen.

Instead, the series started again in 2005, with Christopher Eccleston as the Ninth Doctor. He was replaced by David Tennant at the end of the series. The actor who now plays the Doctor is Jodie Whittaker, who joined the show in the 2017 Christmas episode.

In the Guinness World Records, Doctor Who is listed as the longest running science fiction television series in the world. In 2013, it celebrated its 50th birthday with a special episode.

The Doctor 

The Doctor is the central character of Doctor Who. They are an alien, a Time Lord from the planet Gallifrey. The Doctor often takes other people with them, who are usually called "companions", "assistants" or "friends" (or, due to a misunderstanding, "partners"). They are most often human. The current companions are Yasmin Khan (as played by Mandip Gill), Ryan Sinclair (Tosin Cole) and Graham O'Brien (Bradley Walsh).

As a Gallifreyan, the Doctor looks human on the surface. However, there are differences. For example, they have two hearts. Also, if badly injured or dying, they can regenerate. During the regeneration, their body heals and renews itself. Then, they take on a different appearance and personality. They are the same person (sort of) with the same memories and knowledge. But, they look different and has a new personality. Because of this, the Doctor can be played by different actors. And in over fifty years, this is why the character has not actually "changed".

Incarnations and actors of the Doctor 
Up until now, the Doctor has regenerated fourteen times, and each "incarnation" was played by a different actor (except for the Tenth Doctor, who used up two regenerations by channeling excess regeneration energy after healing to his old hand that had been chopped of in The Christmas Invasion). (Numbers refer to incarnations that used up regenerations).
First Doctor - William Hartnell (1963–1966)
Second Doctor - Patrick Troughton (1966–1969)
Third Doctor - Jon Pertwee (1970–1974)
Fourth Doctor - Tom Baker (1974–1981)
Fifth Doctor - Peter Davison (1981–1984)
Sixth Doctor - Colin Baker (1984–1986)
Seventh Doctor - Sylvester McCoy (1987–1989, 1996)
Eighth Doctor - Paul McGann (1996)
War Doctor - John Hurt (2013)
Ninth Doctor - Christopher Eccleston (2005)
Tenth Doctor - David Tennant (2005–2010) (Regenerated in 2008)
Tenth Doctor - David Tennant (2005–2010) (Regenerated in 2010)
Eleventh Doctor - Matt Smith (2010–2013)
Twelfth Doctor - Peter Capaldi (2013–2017)
Thirteenth Doctor - Jodie Whittaker (starting 2017)

The Doctor has been played by other actors in other media: theatre plays, parodies, etc. These are not officially part of the Doctor Who story.

The movies Dr. Who & the Daleks and Daleks' Invasion Earth 2150 A.D. star Peter Cushing as a human scientist named Doctor Who. Shortly after it was announced that the series would return from its nineties hiatus, Richard E. Grant voiced The Doctor in an animated serial. The BBC issued press releases identifying Grant as the "ninth Doctor" but this was later disregarded by the revived BBC television series.

Sometimes different incarnations of the Doctor meet each other. Usually episodes with several Doctors are made when the program celebrates an anniversary.  In 1973, when the show was 10 years old, the episode "The Three Doctors" was shown. It had the first three Doctors.

In 1983, there was the 20th anniversary special. "The Five Doctors". Patrick Troughton, John Pertwee, Peter Davison and Richard Hurndall (replacing William Hartnell) played The Doctor. Tom Baker refused to play in it, so they used the old footage of the incomplete "Shada" episode to show him.

In 1985, there was the episode "The Two Doctors", with the Second and the Sixth Doctors.

The fifth Doctor met the tenth incarnation in mini-episode named "Time Crash". It was aired in 2007.

The Tenth, Eleventh, and War Doctors met each other in the 50th anniversary special on November 23, 2013. That was the first time the War Doctor was seen. That special had short appearances by all the other Doctors with the use of old, recycled footage. It also had a mysterious version of the Doctor from the far off future played by Tom Baker. The Eighth Doctor also made a return in 2013 for a 50th anniversary special mini-episode.

On August 4, 2013, Peter Capaldi was revealed as the actor who would play the Twelfth Doctor.

The 12th doctor Peter Capaldi met the 1st doctor just before each doctor's regeneration in the last episode of Capaldi's series.

On July 16, 2017, it was revealed that Jodie Whittaker would replace Capaldi as the Doctor. She is the first female Doctor.

In the 2020 episode "Fugitive of the Judoon", Jo Martin was introduced in a surprise twist as the Fugitive Doctor. She is the first black actor to play the Doctor. It is suggested that the Fugitive Doctor is from the Thirteenth Doctor's past.

Another episode from the same year, "The Timeless Children", revealed that there were many incarnations of the Doctor before William Hartnell. The Thirteenth Doctor had forgotten them because the Time Lords had erased her memory.

TARDIS 

The TARDIS (Time And Relative Dimension In Space) is the Doctor's time machine. It can travel to any point in time and space, but the Doctor can never fully control it. The Doctor explains that TARDISes are not built, but they are grown like plants. The TARDIS is alive and has a mind of its own. In the episode The Doctor's Wife when the Doctor is able to communicate directly with its mind, the TARDIS explains that it did not always take him where he wanted to go but that "I always took you where you needed to go."

The TARDIS is bigger on the inside than the outside, which is commented on by almost everyone who enters. On the inside, the TARDIS looks like a giant spaceship, but on the outside it looks like a police telephone box. These telephone boxes were still a common sight in many British cities when the series first began in 1963, but after the walkie-talkie was invented they were no longer needed. They were used by the police as workstations - and people could also use them to call the police.

The Doctor stole the TARDIS from a Time Lord museum when he began his travels. It was described as being a rather old "Type 40" model, whereas the best version is the "Type 70" used by the upper class Time Lords. The TARDIS has a device called the chameleon circuit which is supposed to change its shape on the outside to allow it to disguise it. In the very first story, this device stopped working and left the TARDIS stuck in the shape of a police box.

The farthest the Doctor has ever travelled in the TARDIS is to the Big Bang (the beginning of the Universe) and 100 trillion years into the future (the end of the Universe) (in the episode "Utopia"). The inside of the TARDIS is much bigger than its outside (it is "dimensionally transcendental"). It has a lot of different rooms. The most important of which is the "console room" where the Doctor pilots the TARDIS.

Companions 

The Doctor usually takes other people with them, who are usually called "companions" or "assistants". The Doctor and their companions travel through space and time, have a lot of adventures, and often save many people. The character of the companion was there so that the people watching the series could identify and feel close to a character. The companions were often present-time humans, so people could feel close to them, and they knew as much as the viewers. Because of this, the Doctor could explain things to their companions, and at the same time to the viewers. Almost all the Doctor's companions have been human, or human-looking aliens. Two companions were robots.

Species

The forces for evil 
Overview: The BBC's link to a visual summary of Dr Who's opponents:

The Master 

The Master is a renegade Time Lord. He is the Doctor's nemesis. He was conceived as "Professor Moriarty to the Doctor's Sherlock Holmes". The character first appeared in 1971, played by Roger Delgado. He 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. He 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. The Master was in the three-part finale of the 2007 series, portrayed by Derek Jacobi. He regenerated into John Simm at the end of the episode "Utopia". Simm next appeared in the last (and two-part) episode of the Tenth Doctor in 2009/2010. He then regenerated off-screen into a Time Lady (Michelle Gomez), who returned for the Twelfth Doctor's first series in 2014.

Daleks 

The Daleks are one of the most powerful races in the Doctor Who history. They are the Doctor's worst enemies. They are alien mutants that live inside metal machines that look like pepper pots. Each Dalek casing has an eyesalk, a gunstick and a sucker arm that looks like a plunger. Daleks believe that they should conquer the universe and "exterminate" all other lifeforms that they believe are lesser than them. They can not be easily hurt by guns because their casing reflects or destroys the bullets. They were created on the planet Skaro by an evil scientist named Davros.

The Daleks first appeared in the very first season of Doctor Who, in a serial called "The Daleks" shown between 1963 and 1964. They most recently appeared in the episode "Revolution of the Daleks" in 2021.

Cybermen 

Cybermen are another enemy of the Doctor. They are one of their worst enemies. In the original series, they come from the planet Mondas. In the new series, some of them come from a parallel universe. Cybermen travel across the universe taking people and turning them into machines. They stomp around saying "DELETE!". They kill by electrocution. They are partially vulnerable to the metal gold, and can be killed by gold bullets. They change their look over time, but stay recognizable by "handlebars" on their heads, and tear drops in their eyes.

The Doctor has faced them many times. The first was in "The Tenth Planet" (William Hartnell's last episode). A more recent episode was "World Enough and Time/The Doctor Falls" (the last two episodes of Peter Capaldi's last season).

Sontarans 
The Sontarans are a group of aliens, bred in clone batches, that believe in war over anything else. They must face their enemy in combat because of their weak spot on the back of their neck, the probic vent. They have been said to look like baked potatoes.

The Doctor first met them in The Time Warrior (Jon Pertwee).  They have been on the show and its spinoffs repeatedly.

Earth reptiles 
The Sea Devils and the Silurians lived in the time of the dinosaurs until the catastrophe of the Moon's approach drove them into hibernation. They slept longer than planned and emerged late in the 20th century. The human scientist who discovered the Silurians estimated their era incorrectly. A later Doctor Who story said that they should have been classified as the Eocenes. A second species of hibernating Earth reptiles lived primarily underwater. They were labeled "sea devils" by a frightened, superstitious construction worker who encountered them.

Ice Warriors 
The Ice Warriors are a species of war-like alien who come from the planet Mars. They are human-like green reptiles who can only live in cold climates. The Doctor had to stop them from invading the planet Earth when their home planet became too hot for them to live in. However, they later became a more peaceful species when they joined a group of planets called the Galactic Federation. Other planets in the Federation include Earth and Peladon.

Weeping Angels 
The Weeping Angels are creatures who have existed since the beginning of the universe. Most of them look like stone statues of angels. They can send people back in time by touching them, which they use to feed off energy. They cannot move if someone is looking at them, unless that person looks away or blinks. Anything that looks like an angel can become a Weeping Angel, such as video footage of a Weeping Angel or even the Statue of Liberty.

The forces for good

Time Lords 
The Time Lords are the alien race which the Doctor belongs to. They have two hearts. They can avoid dying by regeneration (transforming their bodies). The Time Lords were in some episodes in the classic series. Sometimes they were allies of the Doctor (at one point he became their president). Other times they were enemies. The Time Lords came from the planet Gallifrey.

When the series returned in 2005, the Time Lords had disappeared in the "Time War". This was a very big war with the Daleks. The Doctor explained that he stopped the war by destroying Gallifrey, killing all of the Time Lords and Daleks. He believed he was the last of the Time Lords, until he discovered that the Master had also survived. Jenny, who was created artificially in The Doctor's Daughter, is not a true Time Lord. For many years, the Doctor felt sorry for destroying Gallifrey. In the 2013 episode The Day of the Doctor, the Doctor learns that he did not actually destroy his planet, but that he had moved it to another universe.

Regeneration 
As of 2018, the Doctor has been played by fourteen actors. They are William Hartnell, Patrick Troughton, John Pertwee, Tom Baker, Peter Davison, Colin Baker, Sylvester McCoy, Paul McGann, John Hurt, Christopher Eccleston, David Tennant, Matt Smith, Peter Capaldi and Jodie Whittaker.

When Time Lords are dying, they "regenerate." This causes a Time Lord's body to completely change, healing itself at the same time. Each time this happens, Time Lords have a different appearance and a different personality. Even with such big changes, Time Lords do not become different people, and will keep their memories each time they "regenerate." This periodic change makes them live a very long time.

A Time Lord is believed to only be able to regenerate 12 times. This means that Time Lords can have a total of 13 different incarnations. This line became stuck in the public consciousness despite not often being repeated, and was recognised by producers of the show as a plot obstacle for when the show finally had to regenerate the Doctor a thirteenth time. The episode "The Time of the Doctor" depicted the Doctor acquiring a new cycle of regenerations, starting from the Twelfth Doctor, due to the Eleventh Doctor being the product of the Doctor's twelfth regeneration from his original set.

A criminal incarnation of the Doctor was somehow spawned between his 12th and final lives - the 'Valeyard'. It tried to sacrifice the sixth Doctor so that he could obtain more "regenerations," allowing himself to live even longer.

The Master was already in his 13th life when he was introduced to the series. His 14th and 15th (and possibly later) incarnations were obtained by taking over the bodies of innocent victims. When the character returned to the show in 2007, the Master was in his 16th (or later) incarnation. Soon, he regenerates into his (~)17th incarnation. Later, he explains that the Time Lords resurrected him to be a great soldier when the Time Lords were fighting the Daleks in the Time War. It is likely that, having been resurrected, he had 12 more regenerations available to him.

A Time Lord can choose not to regenerate. It appears that the process happens all on its own when a Time Lord is dying. But, it can be stopped if the Time Lord does not want to regenerate. This was seen when the (~)17th incarnation of the Master chose to die from a gunshot wound instead of living on as a prisoner in the Doctor's TARDIS.

A Time Lord's body makes a huge amount of energy when regenerating. There is so much of this "regeneration energy" that a Time Lord can regrow a body part that gets removed, as long as it happens soon enough after regenerating. When the Doctor regenerated into his 10th incarnation, his hand was cut off in a sword fight. Because it had been less than 15 hours since he had regenerated into this incarnation, he was able to quickly grow a new hand.

If a Time Lord has kept a part of his or her body that had been removed (like the 10th Doctor's hand, from before), it can be used to keep a Time Lord from changing during regeneration. The 10th incarnation of the Doctor kept the hand that was cut off in the sword fight in a jar on board the TARDIS. Eventually, he was shot by a Dalek, and his body began the regeneration process. After his body had finished healing, but before his body could change into a new one, the Doctor sent all of the extra energy into the hand in the jar.

Related pages

Torchwood
The Sarah Jane Adventures

References

Other websites 

 The Official Website
 

1963 establishments in the United Kingdom
1963 television series debuts
1960s British television series
1970s British television series
1980s British television series
2000s British television series
2000s science fiction television series
2010s British television series
2010s science fiction television series
BBC Television programmes
British science fiction television series
 
Time travel television series
English-language television programs