The Fourth Doctor


 * “What the point of being grown up if you can’t be childish sometimes.”
 * — The Fourth Doctor.

Filled with wanderlust and a renewed curiosity towards exploring time and space, the Fourth Doctor left all ties of his previous incarnation's exile behind on Earth, setting off to travel the universe, taking advantage of his freedom once more.

This incarnation of the Doctor initially travelled with Sarah Jane Smith and Harry Sullivan, but Harry chose to remain on Earth when the opportunity arose. The Doctor and Sarah continued on their adventures until the Doctor was summoned to Gallifrey, necessitating that he leave Sarah Jane behind as humans were not allowed on Gallifrey at the time.

After tangling with the Master on Gallifrey when he tried to heal himself and renew his regeneration cycle, he met and travelled with Leela of the Sevateem. During his travels with Leela, the Doctor gained a new companion in the robot dog, K9. Returning once more to Gallifrey to stop an invasion of Vardans, Leela and the original K9 stayed behind there.

On the White Guardian's orders, the Doctor began looking for the Key to Time with fellow Time Lady Romana and K9 Mark II. Once that search was concluded, the Doctor and Romana went on the run from the Black Guardian. Not long after, Romana regenerated into a new body and continued to travel with the Doctor and K9. When they attempted to answer a Gallifreyan summons, the trio accidentally passed into the smaller universe of E-Space.

During his travels in E-Space, the Doctor gained a new companion in the teenaged mathematical genius Adric. Romana and K9 stayed behind in E-Space as the Doctor and Adric departed for N-Space. There, they encountered a Trakenite named Nyssa and a human named Tegan. The foursome successfully prevented the destruction of the universe by the Master, but only at the cost of this incarnation's life.

The Doctor prepared for the worst when the Watcher, an entity born of his own immediate future, appeared to warn him of his demise. Due to the Master messing with the rotation controls for the Pharos radio telescope, the Doctor fell a great height. Suffering terrible injuries, he was assisted by the Watcher in his last moment, who joined with him and helped him regenerate into his next incarnation.

Season 11

 * Planet of the Spiders

Season 12

 * Robot
 * The Ark in Space
 * The Sontaran Experiment
 * Genesis of the Daleks
 * Revenge of the Cybermen

Season 13

 * Terror of the Zygons
 * Planet of Evil
 * Pyramids of Mars
 * The Android Invasion
 * The Brain of Morbius
 * The Seeds of Doom

Season 14

 * The Masque of Mandragora
 * The Hand of Fear
 * The Deadly Assassin
 * The Face of Evil
 * The Robots of Death
 * The Talons of Weng-Chiang

Season 15

 * Horror of Fang Rock
 * The Invisible Enemy
 * Image of the Fendahl
 * The Sun Makers
 * Underworld
 * The Invasion of Time

Season 16

 * The Ribos Operation
 * The Pirate Planet
 * The Stones of Blood
 * The Androids of Tara
 * The Power of Kroll
 * The Armageddon Factor

Season 17

 * Destiny of the Daleks
 * City of Death
 * The Creature from the Pit
 * Nightmare of Eden
 * The Horns of Nimon
 * Shada

Season 18

 * The Leisure Hive
 * Meglos
 * Full Circle
 * State of Decay
 * Warriors' Gate
 * The Keeper of Traken
 * Logopolis

Season 19

 * Castrovalva
 * Earthshock

20th Anniversary special

 * The Five Doctors

Series 7

 * The Name of the Doctor

2013 Specials

 * The Day of the Doctor

Series 9

 * The Witch's Familiar