Who is Doctor Who? The Definitive Guide (Part 1)

After fifty years on television everything has come back to the first question people ask him: Doctor who?

With 33 seasons already under the belt we’ve learned quite a bit about the British television icon, but if you want the answer to the above question without hundreds of hours of television then look no further.


‘The Doctor’ is an alias adopted by a time travelling alien who has taken an interest in protecting Earth and its history amid his adventures. What his real name is and why he took on the title ‘Doctor’ is something that he has kept to himself, but he does claim that the original Greek medicine practitioners adopted the title in his honour. The Doctor’s homeworld is Gallifrey, whose people refer to themselves as the ‘Time Lords’. One important part of the character’s story that is not often mentioned in the recent seasons is that The Doctor is a fugitive from his homeworld.


The Doctor’s home world of Gallifrey.

Eons before the Doctor began the journey viewers are familiar with two people from Gallifrey – Rassilon and Omega – unlocked the secrets of time travel. They harnessed this power in biomechanical crafts dubbed TARDIS (Time And Relative Dimension In Space) and gave the people of Gallifrey the ability to travel to any point in time and space. Now called the ‘Time Lords’ they quickly adopted a policy of non-interference in history and other cultures and spent their time collecting and recording knowledge. Having grown bored with this routine and frustrated with the Time Lords refusal to use their technology to help people, the Doctor stole a TARDIS from the repair dock and, along with his grand-daughter, went on the run.

Doctor and Susan Foreman

The Doctor and his grand-daughter Susan on the TARDIS.

Only scraps of information about the Doctor’s life prior to the theft of the TARDIS is mentioned during the show. We know some trivial details like him having grown up in a house on the side of a mountain, having been mentored by a hermit living nearby and having spent time at the Time Lord Academy. By all accounts his childhood was a lonely one. He once had a brother and at some time a family but he does not discuss them even when pressed, and their situation remains unclear. When asked if he has any family during his Seventh incarnation the Doctor simply replied “I don’t know”. It is implied that the Doctor and the Master were friends in their youth until gazing into the time vortex drove the Master insane.

In appearance the Doctor resembles a human, but there are some differences. The most notable physical difference between Time Lords and humans is that the former have two hearts, one on either side of their chest. They also have some latent telepathic ability, but nothing to the degree that they can manipulate people.


The particular craft stolen by the Doctor is a Class TT Type 40, Class 1 – generally considered to be obsolete by the Time Lords. The Doctor stole it from the repair yards along with his grand-daughter Susan after they’d decided that they’d had enough of the Time Lord attitude towards time travel. Although appearing small on the outside, the interior of a TARDIS is substantially larger. It’s roughly the size of the Empire State Building, but with the ability to expand to infinite size. The interior is constructed with a living metal that can create new rooms as needed. Among the rooms already created in the TARDIS are a study, an extensive library, squash courts, quarters for each companion and a swimming pool. Most of the action takes place within the console room from which the TARDIS is piloted. The main features of the console is a hexagonal control deck and a central pillar that moves in and out when the TARDIS is in flight. As the shape of the console suggests the ideal number of pilots is six, which goes some way to explain why the Doctor so frequently winds up in the wrong place and time.

TARDIS Console room

The Doctor and Leela in the console room.

Originally the exterior of the TARDIS was a plain grey tube. Every TARDIS is equipped with a chameleon circuit that will change the outward appearance of the vessel to help it blend in with its surroundings. One of the initial stops by the Doctor with his stolen TARDIS was London during the 1960s to allow Susan the chance to attend school on Earth. The TARDIS took the form of a common police box (although it was parked in a scrapyard) and the chameleon circuit jammed. Although the Sixth incarnation of the Doctor did attempt to get it working again the blue police box disguise has become its permanent form.

The TARDIS is powered by an exploding star that is in the process of collapsing into a black hole. The star is kept in a state of stasis and permanent decay in order to provide the massive amount of energy required to propel the craft through space and time. Rather than being built, the TARDIS is grown from a rare form of coral that grows on Gallifrey. The process of constructing this matter into a ship has never been discussed.


The ‘Eye of Harmony’, which powers the TARDIS.


One of the most distinct abilities held by the Time Lords is ‘regeneration’. When drastically injured or near death the Time Lords regenerate their bodies, creating a new appearance and to some degree a new personality. Whilst the Doctor’s core beliefs – such as pacifism and faith in humanity – remain intact, his attitude and quirks will change. It has been noted several times that each Time Lord can go through twelve different forms before dying, but it has also been suggested that this limit can be extended through Time Lord technology if the need arises. The process expends a large amount of time energy, and on a few occasions it has been implied that this energy can be redirected to other beings if a Time Lord sacrifices future incarnations.

Doctor Who Regeneration

The Tenth Doctor begins his regeneration.

The Doctor has undergone ten regenerations during the course of the series, with two cases of hidden incarnations (the Valeyard during Trail of a Time Lord and the recently revealed incarnation during The Name of the Doctor) yet to be revealed. During the show The Master, Romana, River Song and K9 have all undergone regenerations, with Romana demonstrating that some Time Lords have the ability to control their appearance.

So who are the Doctors?

The First

Played by William Hartnell

The Cantankerous Grandfather

Years Active: 1963-1966

Appearance: An elderly, silver haired gentleman with shoulder length hair. He appeared to be quite frail but often proved to be more formidable than the initial impression. The First would dress in a muddled Edwardian style of dress and carried a cane with a twisted top.

Skills: The First Doctor was equipped with an exceptional intellect and encyclopaedic knowledge of human history, and would rely on his wits to see him through trouble.

Catchphrase: “Mmm? What’s that my boy?”

Personality: Not only the first Doctor to appear on television but the Doctor’s original form. Although he is the Doctor at his youngest in the characters chronology his is the oldest physical appearance. From the outset he comes across as a rather grumpy and cantankerous character, quite demanding of people and insisting they follow his lead. As his companions spent more time with him they found that they warmed up to him and respected his wisdom and strength of will even if he was abrupt at times. His love of travel and adventure was always his driving force and his spirit would be contagious.

First Doctor TARDIS

Piloting the TARDIS with Ian, Barbara and Susan.

Companions: The First was never lacking for company. He arrived on Earth with his grand-daughter Susan, and they were joined by school teachers Ian and Barbara. Along for the ride at various stages were Vicki and Steven, both from different points in Earth’s future, Katarina and Sarah who perished before long, orphan girl Dodo and modern Earthlings Polly and Ben.

Key Events: The most significant part of the First Doctor’s story was stealing the TARDIS from Gallifrey and setting off on an adventure that would span centuries and reshape the history of the universe.

First Doctor steals TARDIS

The Doctor being confronted by Clara while stealing the TARDIS.

During his travels the First Doctor crossed paths with many figures of note from throughout history including (but not limited to) Marco Polo, Nero, Saladin, Kublai Khan, Catherine de’ Medici, William Shakespeare, Napoleon, Wyatt Earp, Charlie Chaplin, Cassandra, Achilles, Agamemnon and Odysseus. During these encounters he would become involved in events such as the Crusades and Nero’s burning of Rome.

When he wasn’t mingling with famous figures of history, he was making enemies. Early in his journey the Doctor encountered the Daleks on their home planet of Skaro and later repelled their first attempt to conquer Earth. He also battled against the Cybermen for the first time when they attacked a base in the South Pole.

Regeneration: During his first encounter with the Cybermen the Doctor commented that he was feeling run down. After returning to the TARDIS he collapsed on the floor and underwent a change into his Second incarnation.

The Second

Played by Patrick Troughton

The Cosmic Hobo

Years Active: 1966-1969

Appearance: A diminutive character with a mop of dark hair, the Second incarnation was notably younger than the First. He would dress in a similar manner, if a tad more scruffy and with a bow tie, as the First and sometimes don a thick fur coat in colder climes. The Second Doctor also carried a recorder that he would play from time to time.

Skills: The Second Doctor has the same intellectual capacity as the First but would channel his mind towards playful manipulations and scheming. He would often be several steps ahead of his enemy and play them into traps. He is an avid puzzle solver and would delight in solving mathematical equations.

Catchphrase: “When I say run…RUN!” and “Oh my giddy aunt.”

Personality: Certainly a friendlier character than the original version of the character, the Second would take a childlike delight in his adventures. Even when faced with attempting to solve a series of puzzles to escape an attack of the Cybermen he would solve them behind his companions backs and wait to see how well they did of their own accord. Rather than take a hostile approach with his foes, the Second would often give them a runaround and let them fall into a trap. His love of over-the-top head gear and playing his recorder marked him as something of a clown.

Companions: Of the travelers who joined the Second Doctor it’s the highlander Jamie who stayed the longest. The two companions formed a tight bond with the Doctor’s intellect balancing out Jamie’s readiness to leap into action. After Ben and Polly returned to Earth they were briefly joined by Victoria, an aristocratic lady who balked at the danger they faced. Finally there was Zoe, whose intellect and understanding of psychics almost matched the Doctor’s. Jamie and Zoe were with the Doctor up until his original trail, after which their memories were erased.

Second Doctor

In the field with Jamie and Victoria.

Key Events: After regenerating the Second Doctor faced Daleks and Cybermen again. Along with these classic foes the Second also battled against the Ice Warriors from Mars who would attack Earth on more than one occasion.

The Second Doctor didn’t meet as many famous figures as the First, but he did encounter Blackbeard the Pirate.

At the end of his involvement in the War Games, the Doctor was returned to Gallifrey to stand trail for stealing a TARDIS. The punishment involved being exiled to Earth.

Regeneration: Before being returned to Earth, the Time Lords forced a regeneration on the Doctor. He changed his appearance during the trail, against his will, and was sent along with the disabled TARDIS to England.

The Third

Played by John Pertwee.

The Dandy

Years Active: 1970-1974

Appearance: Taller and stronger in stature than his previous forms, the Third Doctor was a charismatic and commanding presence. He was a very dapper dresser with velvet smoking jackets, leather shoes and gloves, and frilled shirts and capes. Although the Sonic Screwdriver made its first appearance with the Second Doctor, it was used more regularly by the Third. He was also known for his bright yellow, gadget packed old roadster, Bessie, and later his ‘Whomobile’ hovercraft.

Skills: The Third was best known as a hands-on scientist, spending much of his time in the UNIT labs working on repairing the TARDIS. He would envision and build many gadgets and new technologies during his exile on Earth.

Catchphrase: “Reverse of polarity of the neutron flow!” and “Now listen to me…”

Personality: A bold and outspoken character, the Third could seem to be talking down to his companions. In spite of this perception he was a warm hearted personality. He had little patience for bureaucrats and ministers and would form a better relationship with his assistants in the lab. He could be quite waspish and impatient with people, demanding that they take heed of his knowledge and advice at all times. The Third was also more physically daring and more likely to confront his foes head on, even holding a grudging respect for his frequent sparring partner The Master.

Doctor Who and the Master

In the TARDIS with the original incarnation of The Master (Roger Delgardo).

Companions: The ever suffering Brigadier of UNIT would be a constant feature during the Doctor’s time on Earth as the Doctor acted as scientific advisor to the organisation. His first assistant in the laboratory is Liz Shaw who was quickly replaced by Jo Grant. The two had a tight bond until she left to be married with Sarah Jane Smith, an aspiring journalist, joining the Doctor not long after.

Key Events: The exile to Earth was the most significant moment of this era, with the Doctor only returning the TARDIS to full functionality two thirds of the way through his run. Whilst on Earth he would encounter many new and deadly foes including the Silurians and Sea Devils, the Sontarian and the Autons. Most important was the introduction of The Master, an insane Time Lord bent on conquering the universe. This rival figure would be quick to establish himself as the Doctor’s arch-enemy and they would battle many times.

Regeneration: After defeating the giant spiders and the Great One who ruled over them, the Doctor is washed over by a wave of radiation. The Doctor escapes to the TARDIS and returns to Earth, but collapses on arrival and begins his regeneration.

Stay tuned for Volume 2 – gadgets, enemies and the next four Doctors!