The Doctor

Lore & Background

The Fourth Doctor is a centuries-old alien Time Lord from the planet Gallifrey who travels in time and space in the TARDIS. He is portrayed by Tom Baker. His initial companions were the journalist Sarah Jane Smith (Elisabeth Sladen), who had travelled with his previous incarnation, and Surgeon-Lieutenant Harry Sullivan (Ian Marter) of UNIT. His later companions were the warrior Leela (Louise Jameson), robotic dog K9 (John Leeson and David Brierly), fellow Time Lady Romana (Mary Tamm and Lalla Ward), teen mathematical genius Adric (Matthew Waterhouse), teen alien aristocrat Nyssa (Sarah Sutton), and Australian flight attendant Tegan Jovanka (Janet Fielding). Baker portrayed the character for seven consecutive seasons, which remains the longest tenure of any actor to portray the lead, counting both the classic and new series.

In Their Own Story

After contracting radiation poisoning from the crystals of the planet Metebelis 3, the Third Doctor regenerates into the Fourth Doctor (Planet of the Spiders). In his new incarnation, the Doctor is eager to leave Earth in favour of exploration. He travels with journalist Sarah Jane Smith and, for a time, with UNIT Surgeon-Lieutenant Harry Sullivan. The Doctor's companionship with Sarah Jane came to an end when he received a telepathic summons to Gallifrey, which turns out to be part of a trap set by his enemy the Master. The Doctor is framed for the assassination of the President of the High Council of Time Lords and put on trial. To avoid execution, the Doctor invokes an obscure law and declares himself a candidate for the office, giving himself the time he needs to prove his innocence and expose the real culprit (The Deadly Assassin). The Doctor is seen to travel alone for the first time, returning to a planet he had visited centuries before. After the Doctor cures the computer Xoanon, one of the Sevateem, Leela, joins him on his travels (The Face of Evil). Later, the Doctor and Leela visit the Bi-Al Foundation medical centre, where they acquire the robot dog K-9 (The Invisible Enemy). Eventually, the Doctor returns to Gallifrey and declares himself Lord President, based on the election held during his previous visit. This is in fact a ploy to reveal and defeat a Vardan invasion plan, which led to the unexpected consequence of leaving Gallifrey open to attack by the Sontarans (The Invasion of Time). In the aftermath Leela and K9 decide to remain on Gallifrey. The Doctor comforts himself by producing K9 Mark II. Shortly afterward, the powerful White Guardian assigns the Doctor the task of finding the six segments of the Key to Time, sending a young female Time Lord named Romana (as portrayed by Mary Tamm) to assist him. After the conclusion of the quest, Romana regenerates into a new form (portrayed then by Lalla Ward) (Destiny of the Daleks). In an effort to evade the Black Guardian, the Doctor installs a 'Randomiser' in the TARDIS. The Doctor and Romana are projected outside the known universe and into a universe of negative coordinates, known as Exo-Space. The TARDIS lands on a planet called Alzerius (Full Circle), where they are joined by a young prodigy named Adric. Eventually, the Doctor and his two companions find themselves in a white void with no coordinates, a sort of membrane between the two universes. A way out soon forms, but Romana and K-9 choose to remain behind to help free a race of enslaved creatures in E-Space (Warriors' Gate). The Doctor and Adric have only just made it back when they're asked to help the people of Traken from a creature known as 'Melkur.' On Traken, Adric and the Doctor are introduced to the aristocratic teen Nyssa of Traken. The Doctor decides to travel to Earth to scan a real Police Box as part of a plan to repair the 'Chameleon Circuit'. As the Doctor prepares to travel to the planet Logopolis to get the Chameleon Circuit fixed, Tegan Jovanka appears in the console room. Logopolis soon falls under the Master's control, but the stasis field he is generating ends up releasing Entropy and eroding matter throughout the universe, threatening to destroy the entire universe. The Master agrees to help the Doctor stop the spread of Entropy by adapting the Pharos Project radio telescope on Earth. When the Master tries to take control of it, the Doctor runs out under the upturned radio dish to sever the cable linking the Master to the CVEs. The Master makes the dish start rotating so that the Doctor will fall to his death. Before he falls, he manages to tear out the cable, only to leave his companions watching as he clings to the cable. As his grip begins to slip, he sees visions of all the enemies he's faced over the years, then falls. Adric, Nyssa, and Tegan gather around the mortally wounded Doctor and call out his name. He then looks up at the three of them and utters his last words: 'It's the end — but the moment has been prepared for...' He then motions to the white-clad figure of the Watcher, who begins approaching the Doctor. The Watcher, a manifestation of the Doctor's future incarnation, merges with the Doctor and triggers his regeneration.

Reader's Guide

The Fourth Doctor is a Time Lord who travels in time and space in the TARDIS. He is portrayed by Tom Baker for seven consecutive seasons, the longest tenure of any actor to portray the lead. His initial companions were Sarah Jane Smith and Harry Sullivan. Later companions included Leela, K9, Romana (portrayed by Mary Tamm and later Lalla Ward), Adric, Nyssa, and Tegan Jovanka. Key events in his tenure include: being framed for assassination and declaring himself a candidate for President of the High Council of Time Lords (The Deadly Assassin); acquiring K9 (The Invisible Enemy); being assigned by the White Guardian to find the six segments of the Key to Time; entering Exo-Space (Full Circle); and his final battle with the Master on Logopolis, where he falls from the Pharos Project radio telescope and regenerates into the Fifth Doctor.

Did You Know?

• Tom Baker portrayed the Fourth Doctor for seven consecutive seasons, the longest tenure of any actor to portray the lead in both the classic and new series.
• The Fourth Doctor's initial companion Sarah Jane Smith had already travelled with his previous incarnation, the Third Doctor.
• The Fourth Doctor acquired the robot dog K-9 at the Bi-Al Foundation medical centre (The Invisible Enemy).
• The Fourth Doctor was assigned by the White Guardian to find the six segments of the Key to Time, and was assisted by the Time Lady Romana.
• The Fourth Doctor's last words before regenerating were: 'It's the end — but the moment has been prepared for...'