The First Doctor (1963-1966)
Season 
One (1963-64) Season One (1963-64): Into The Vortex
First appearances of the Doctor, Susan, Ian, Barbara, the TARDIS, the Daleks and the Thals.
Season Two 
(1964-65) Season Two (1964-65): Flight Through Eternity
First appearances of Vicki, Steven and the Meddling Monk. The Monk is the first member of the Doctor's own people to be introduced, apart from Susan and the Doctor himself.
Season 
Three (1965-66) Season Three (1965-66): Turbulence
First appearances of Katarina, Sara, Dodo, Polly and Ben.
Season 
Four (1966) Season Four (1966): Wearing A Bit Thin
First appearance of the Cybermen. The Doctor regenerates for the first time.

Season One (1963-64): Into The Vortex

The Doctor
The First Doctor

William Hartnell (bio) made his first appearance as the Doctor in 100,000 BC (November 1963) and his last in The Three Doctors (January 1973).

Companions and Recurring Characters

Susan (who often used the last name “Foreman”) was the Doctor's first travelling companion; she was also his grandchild.

Carole Ann Ford (bio) made her first appearance as Susan in 100,000 BC (November 1963) and her last in Dimensions In Time (November 1993).

Susan

Ian Chesterton was Susan's science teacher whom the Doctor kidnapped from 1963 England along with his colleague, Barbara Wright.

William Russell (bio) made his first appearance as Ian in 100,000 BC (November 1963) and his last in The Power Of The Doctor (October 2022).

Ian Chesterton

Barbara Wright was a history teacher from 1963 England who, like Ian Chesterton, found herself being abducted into time and space by the Doctor.

Jacqueline Hill (bio) made her first appearance as Barbara in 100,000 BC (November 1963) and her last in The Chase (June 1965).

Barbara

The Production Team

Throughout the original 1963-1989 run of Doctor Who, the production team primarily consisted of a producer and a story editor (later called a script editor). Doctor Who's first producer was Verity Lambert (bio), a novice in the position who was brought to the BBC by series creator Sydney Newman. To help guide Lambert, BBC veteran Mervyn Pinfield (bio) was installed in the role of associate producer. David Whitaker (bio), another reliable BBC hand, was Doctor Who's first story editor.

The Stories
100,000 
BC
100,000 BC by Anthony Coburn, directed by Waris Hussein
Intrigued by a strange pupil named Susan Foreman, schoolteachers Ian Chesterton and Barbara Wright follow her home one night. “Home” turns out to be a time machine called the TARDIS, its police box disguise concealing an immense interior. Susan's grandfather, the Doctor, becomes determined to prevent Ian and Barbara from unmasking them as alien wanderers in time and space. Activating his temperamental ship, the Doctor catapults them back into humanity's prehistory. There the four are captured by a tribe of cavemen, to be sacrificed as a means of regaining the lost secret of making fire. (Also known as An Unearthly Child and The Tribe Of Gum.)
Ian and Barbara join the Doctor and Susan in their travels.
The 
Daleks
The Daleks by Terry Nation, directed by Christopher Barry and Richard Martin
The TARDIS brings the travellers to Skaro, a world devastated by the radioactive fallout of a long-ago war, which has mutated its two native races in very different ways. The Thals are now beautiful and peace-loving, while the Daleks have become cunning, xenophobic monsters housed inside travel machines. The Thals save the four newcomers from radiation poisoning, but the Daleks are plotting to exterminate their ancient enemies. The Doctor is determined not to intervene... until he realises that the Daleks are in possession of a vital TARDIS component. (The serial's actual title is The Mutants, but this is generally avoided due to the potential confusion with 1972's The Mutants. Also known as The Dead Planet.)
Inside The 
Spaceship
Inside The Spaceship by David Whitaker, directed by Richard Martin and Frank Cox
Something is very wrong with the TARDIS. After an explosion knocks everyone unconscious, its four occupants awaken to find the time machine malfunctioning in strange ways. The doors open to reveal a white void, clock faces melt, and the scanner screen displays a baffling series of images. To make matters worse, those aboard behave in an increasingly erratic, paranoid and even violent manner. Has some strange force invaded the TARDIS, or is one of the time travellers actually sabotaging the Ship? As hysteria mounts and the seconds slip away, they find themselves on the brink of disaster. (Also known as The Edge Of Destruction and Beyond The Sun.)
Marco 
Polo
Marco Polo by John Lucarotti, directed by Waris Hussein and John Crockett
The TARDIS lands in 1289 China. There it is seized by explorer Marco Polo, who intends to present it as a gift to Kublai Khan, in the hope that it will win him his freedom. The Doctor, Susan, Ian and Barbara will have to accompany Polo as he travels across the desert to the court in Peking. Susan befriends a young girl in the caravan named Ping-Cho, who is heading towards an arranged marriage. Also accompanying Polo is Tegana, an emissary of a rival warlord. While claiming to seek peace with Kublai Khan, Tegana's true mission is to assassinate the Khan, imperilling the lives of Polo and all those journeying with him. (All seven episodes are missing.)
The Keys Of 
Marinus
The Keys Of Marinus by Terry Nation, directed by John Gorrie
Many years ago, the people of the planet Marinus developed the Conscience, a computer with the power to control minds. It was used only to keep the peace until Yartek, leader of the evil Voords, overcame its influence. To prevent Yartek from using the Conscience as a weapon, the five keys that power it were hidden. Now the scientist Arbitan believes he can defeat Yartek and compels the Doctor, Susan, Ian and Barbara to embark on a quest to recover the keys. But many dangers lie between the companions and their goal: hypnotic monsters, killer plants, ice zombies, and finally a charge of murder.
The 
Aztecs
The Aztecs by John Lucarotti, directed by John Crockett
In 1430 South America, Barbara is mistaken by the Aztecs as the reincarnation of the High Priest Yetaxa. Now regarded as a living deity, Barbara realises that she could change history and end the Aztec practice of human sacrifice. But while Barbara has the loyalty of Autloc, the High Priest of Knowledge, she is mistrusted by Tlotoxl, the High Priest of Sacrifice. Scheming to disprove Barbara's divinity, Tlotxl kindles a rivalry between Ian and a mighty Aztec warrior, and ensures that Susan is chosen to wed a sacrificial victim. And how will the Doctor react to Barbara's decision?
The 
Sensorites
The Sensorites by Peter R Newman, directed by Mervyn Pinfield and Frank Cox
The TARDIS lands on an Earth spaceship orbiting the Sense-Sphere, its crew held prisoner by the telepathic Sensorites. The time travellers are able to make peaceful contact with the reclusive Sensorites, and learn that there has been a wave of deaths on the Sense-Sphere ever since another human expedition landed ten years earlier. The Doctor sets out to discover what has been killing the Sensorites... and his need becomes all the more urgent when Ian's health begins to fail. At the same time, he must contend with the machinations of a Sensorite who sees the chaos as the chance to seize power for himself.
The Reign Of 
Terror
The Reign Of Terror by Dennis Spooner, directed by Henric Hirsch
The four companions find themselves in eighteenth-century France, during the dying days of Robespierre's blood-drenched Reign of Terror. Ian, Barbara and Susan are captured by soldiers of the Revolutionary Army and thrown into a grubby prison run by an enigmatic governor named Lemaitre. The women are sentenced to death at the guillotine, while a dying spy entrusts Ian with a vital message. Meanwhile, the Doctor poses as a member of the new ruling elite and embarks on a mission to save his friends. But in a land of suspicion where hidden agendas abound, can anyone be trusted to help? (Episodes four and five are missing.)

Making History

Doctor Who was created in response to a long-identified need for a family show to bridge the gap in the BBC's Saturday evening schedule, between afternoon sports coverage and teenage-oriented music programming. The brainchild of new BBC Head of Drama Sydney Newman, few gave the science-fiction series a chance to succeed. But ratings skyrocketed following the introduction of the Daleks in Doctor Who's second adventure, securing the programme's place in the schedule. In the span of mere weeks, Doctor Who became a household name, and an enduring television phenomenon was born.

Season Two (1964-65): Flight Through Eternity

Companions and Recurring Characters

Vicki was an orphan from the twenty-fifth century who was rescued from the planet Dido by the Doctor.

Maureen O'Brien (bio) made her first appearance as Vicki in The Rescue (January 1965) and her last in The Myth Makers (November 1965).

Vicki

Steven Taylor was a space pilot from the future whom the Doctor met on the planet Mechanus.

Peter Purves (bio) made his first appearance as Steven in The Chase (June 1965) and his last in The Savages (June 1966).

Steven Taylor

The Production Team

With Verity Lambert now firmly installed as producer, Mervyn Pinfield left Doctor Who midway through Season Two. David Whitaker, too, departed early in the season, to be succeeded by Dennis Spooner (bio). Spooner worked diligently to expand Doctor Who's horizons by introducing new elements such as comedy into the series. Toward the season's end, Spooner also left the show and Donald Tosh (bio) became script editor.

The Stories
Planet 
Of Giants
Planet Of Giants by Louis Marks, directed by Mervyn Pinfield and Douglas Camfield
When the doors of the TARDIS open in mid-flight, its occupants are reduced to just inches in height. They land in an English country garden, where the unscrupulous Forester plans to profit from a powerful new insecticide called DN6. However, when a government representative named Farrow discovers that DN6 will have devastating effects on the environment, Forester shoots him dead. Despite their diminutive size, the time travellers must find a way to bring Forester to justice -- even as Barbara begins to succumb to the poisonous effects of DN6.
The Dalek 
Invasion Of Earth
The Dalek Invasion Of Earth by Terry Nation, directed by Richard Martin
The Doctor, Susan, Ian and Barbara find themselves on Earth in the middle of the twenty-second century... and the Daleks have invaded. Now the streets of London are stalked by the Daleks' brainwashed human puppets -- the Robomen -- while more terrible monsters roam the countryside. Ian stows away aboard a Dalek saucer, while the others forge an uneasy alliance with a desperate band of freedom fighters, led by the scientist Dortmun. But in order to reclaim the planet for humankind, they must first uncover the true purpose of the Daleks' massive mining operations in Bedfordshire.
Susan stays behind with rebel David Campbell.
The 
Rescue
The Rescue by David Whitaker, directed by Christopher Barry
An Earth spacecraft has crashlanded on Dido in the year 2493, and most of its crew has been murdered by the planet's denizens. The only survivors are Bennett, crippled and bedridden, and an orphaned girl named Vicki. They are now being terrorised by the monstrous Koquillion while they wait for a rescue ship to arrive. When the TARDIS lands on Dido, the Doctor expects to meet a peaceful native race, and is baffled that the planet seems all but deserted. When Koquillion tries to kill them, the time travellers become determined to discover his true motives, and his real identity.
Alone in the world, Vicki joins the TARDIS crew.
The 
Romans
The Romans by Dennis Spooner, directed by Christopher Barry
Whilst vacationing in AD 64 Rome, Ian and Barbara are kidnapped and sold as slaves. Ian ends up on a doomed galley ship, while Barbara becomes a handmaiden in Nero's palace, pursued by the lusty Caesar himself. Meanwhile, the Doctor and Vicki are travelling to Rome, unaware of their friends' plight. On the road, they discover the body of a murdered musician named Maximus Pettulian. The Doctor decides to investigate by masquerading as Pettulian, unaware that he is embroiling himself in a conspiracy against Nero -- and in the events which culminate in the Great Fire of Rome.
The Web 
Planet
The Web Planet by Bill Strutton, directed by Richard Martin
A strange force draws the TARDIS to the desolate planet Vortis. Barbara is compelled to leave the time machine, and is rescued by the butterfly-like Menoptra, who have returned from outer space to retake their planet from an alien force called the Animus. The Animus has ravaged Vortis and taken control of its lower animal life, including giant ants called the Zarbi. The Zarbi steal the TARDIS with Vicki inside, and carry it to the Carsenome, the Animus' terrible lair. There the Doctor is compelled to assist in repelling the Menoptra invasion: the final stage in the Animus' global conquest.
The 
Crusade
The Crusade by David Whitaker, directed by Douglas Camfield
In twelfth-century Palestine during the Third Crusade, the time travellers stumble into an attempt by the sinister El Akir to kidnap King Richard the Lionheart on behalf of Saladin, the Saracen ruler. Although Richard is saved, Barbara is captured. The Doctor, Ian and Vicki implore Richard to rescue their friend -- even winning the support of the King's sister, Joanna -- but the Lionheart's pride makes him hostile to any suggestion that he negotiate with his sworn enemies. And while Saladin treats Barbara kindly, she has caught the eye of El Akir, whose intentions are far less noble. (Episodes two and four are missing.)
The Space 
Museum
The Space Museum by Glyn Jones, directed by Mervyn Pinfield
The TARDIS lands at a space museum on the planet Xeros. The four companions set out to explore, but quickly realise that something is very odd: they leave no tracks, they can't touch anything, and nobody in the museum reacts to their presence. When they find themselves displayed as exhibits, the Doctor realises that they have jumped a time track, and are glimpsing their own future. When time catches up with them, they have no choice but to ally themselves with the native Xerons against the warlike Moroks who rule the planet, if they're to have any hope of averting their horrible destiny.
The 
Chase
The Chase by Terry Nation, directed by Richard Martin
On the desert planet Aridius, Ian and Vicki go exploring while the Doctor and Barbara enjoy the sun. However, the companions are unaware that the Daleks have constructed their own time machine, and are determined the hunt down the TARDIS. The Daleks land amidst a terrible sandstorm, forcing the Doctor and Barbara to seek help from the native Aridians in locating Ian and Vicki, who are menaced by terrible Mire Beasts. But Aridius is just the first stop in a desperate chase through time and space, which will lead to the Empire State Building, the Mary Celeste, a haunted house, and beyond.
Barbara and Ian return to their own time in the Dalek time machine, while space pilot Steven Taylor joins the Doctor and Vicki.
The Time 
Meddler
The Time Meddler by Dennis Spooner, directed by Douglas Camfield
The TARDIS brings the Doctor, Vicki and Steven to 1066 England, on the outskirts of a Saxon village, where they stumble across technology centuries ahead of its time. The Doctor discovers that a nearby monastery is now home to a time-travelling member of his own race, one with a penchant for interfering in established history. With the Battle of Hastings imminent, this erstwhile Monk has been tracking the Viking fleet that has been harassing the Saxons. He intends to destroy it using advanced weaponry -- positioning King Harold to defeat William the Conqueror, and irrevocably altering Earth's future.

Making History

Despite losing much of its original cast and production team -- by the season's end, only William Hartnell and Verity Lambert were left of the original roster -- Doctor Who thrived amidst all the changes. The return of the Daleks, in response to furious demands from fans across Britain, simply fuelled the fire that had been ignited by the original appearance of the mutants from Skaro. Dalek merchandise was soon all but unavoidable, with a weekly comic strip and even a feature film manifesting as the season progressed.

Season Three (1965-66): Turbulence

Companions and Recurring Characters

Katarina was a Trojan handmaiden who met the Doctor during the events surrounding the Greek siege of Troy.

Adrienne Hill (bio) made her first appearance as Katarina in The Myth Makers (November 1965) and her last in The Daleks' Master Plan (December 1965).

Katarina

Sara Kingdom was a Space Special Security agent in the forty-first century, who allied herself with the Doctor after discovering that she had been manipulated by the treacherous Mavic Chen.

Jean Marsh (bio) played Sara in The Daleks' Master Plan (December 1965 to January 1966).

Sara Kingdom

Dorothea (Dodo) Chaplet -- who may have been a descendant of the Doctor's friend Anne Chaplet, who lived at the time of the 1572 Huguenot Massacre -- was a mid-Sixties British schoolgirl who accidentally wandered into the TARDIS.

Jackie Lane (bio) made her first appearance as Dodo in The Massacre Of St Bartholomew's Eve (February 1966) and her last in The War Machines (July 1966).

Dodo Chaplet

Polly was a young secretary in 1966 London who first encountered the Doctor when she became a pawn of the evil computer WOTAN.

Anneke Wills (bio) made her first appearance as Polly in The War Machines (June 1966) and her last in The Faceless Ones (May 1967).

Polly

Ben Jackson was a merchant seaman who befriended the Doctor during the computer WOTAN's attack on 1966 London.

Michael Craze (bio) made his first appearance as Ben in The War Machines (June 1966) and his last in The Faceless Ones (May 1967).

Ben Jackson

The Production Team

Early in Season Three, Verity Lambert stepped down as producer and was succeeded by John Wiles (bio). With Donald Tosh, Wiles attempted to remould Doctor Who as a more serious, less juvenile science-fiction programme, but they came into conflict with William Hartnell. With BBC management on Hartnell's side, Wiles and Tosh tendered their resignations. Their replacements were Innes Lloyd (bio) as producer and Gerry Davis (bio) as script editor. They instead sought to emphasise the “science” in “science-fiction”, even bringing aboard Dr Kit Pedler as Doctor Who's unofficial scientific advisor.

The Stories
Galaxy 4
Galaxy 4 by William Emms, directed by Derek Martinus
When the TARDIS lands on a barren world, the three companions emerge to find a robot that Vicki nicknames a Chumbley. They are rescued from the Chumbley by the beautiful Drahvins; their leader, Maaga, explains that the robot serves their hideous enemies, the Rills. The Drahvins and the Rills were engaged in a battle in space when they both crashlanded on this planet -- a planet that is on the verge of exploding. But even as the Drahvins start using increasingly strong-arm tactics to get the time travellers to help them, the Doctor discovers that the planet's doom is not days away... but mere hours. (Episodes one, two and four are missing.)
Mission To 
The Unknown
Mission To The Unknown by Terry Nation, directed by Derek Martinus
A spaceship captained by Gordon Lowery has landed on Kembel. One of his fellow astronauts, Jeff Garvey, becomes infected by a Varga plant, and is consumed with homicidal rage even as he starts to turn into a Varga plant himself. Garvey is killed by the ship's other passenger, Marc Cory, who reveals that he is an agent of the Space Security Service. His mission is to expose a Dalek plot being hatched at a secret base on Kembel -- one that involves a conspiracy spanning the stars. But with Daleks bearing down on him, and Lowery also succumbing to the Varga infection, can Cory survive to warn the galaxy? (Also known as Dalek Cutaway. This episode is missing.)
The Myth 
Makers
The Myth Makers by Donald Cotton, directed by Michael Leeston-Smith
For years, the city of Troy has been besieged by Greek forces, but now both sides are growing weary of the conflict. When the TARDIS materialises, the Doctor is mistaken for the god Zeus, but he soon attracts the suspicions of the wily Odysseus. News soon comes that the Trojans have captured the TARDIS -- with Vicki still inside. Steven agrees to infiltrate Troy, while the Doctor is tasked with devising a scheme to achieve victory for the Greeks, once and for all. Inside the walls of Troy, Vicki finds romance with Troilus, youngest son of King Priam. But Troilus' sister, Cassandra, prophesies doom in the shape of a horse... (All four episodes are missing.)
Vicki remains with Troilus, while handmaiden Katarina helps a wounded Steven into the TARDIS.
The Daleks' 
Master Plan
The Daleks' Master Plan by Terry Nation and Dennis Spooner, directed by Douglas Camfield
On the planet Kembel, the Doctor meets Space Security Service agent Bret Vyon, who is searching for his missing colleague, Marc Cory. They learn that Cory was murdered by the Daleks, who have formed a vast intergalactic alliance -- of which Mavic Chen, the traitorous Guardian of the Solar System, is a member. The Daleks plan to use a time destructor to take over the universe, but the Doctor steals the taranium core needed to fuel it. The Doctor, Steven, Katarina and Bret are soon pursued across time and space by the Dalek forces... including Bret's own sister, fellow agent Sara Kingdom. (Episodes one, three, four, six through nine, eleven and twelve are missing.)
Katarina sacrifices herself to save the Doctor and Steven; Sara becomes a TARDIS traveller, but perishes due to the effects of the time destructor.
The Massacre 
Of St Bartholomew's Eve
The Massacre Of St Bartholomew's Eve by John Lucarotti and Donald Tosh, directed by Paddy Russell
The TARDIS lands in 1572 Paris. While the Doctor visits an apothecary named Charles Preslin, Steven befriends two Huguenots in the service of Admiral de Coligny, who is loyal to France's Protestant prince, Henry of Navarre. They meet Anne Chaplet, a servant employed by the Abbot of Amboise. Anne reveals that the Abbot is helping plan a slaughter of Huguenots: a massacre sanctioned by Catherine de Medici, the King's mother. But when Steven discovers that the Abbot looks just like the Doctor, he must determine whether this is really his friend in disguise -- and, if so, the role he must play in the terrible events. (Also known as The Massacre. All four episodes are missing.)
In 1966, schoolgirl Dodo Chaplet accidentally stumbles into the TARDIS.
The Ark
The Ark by Paul Erickson and Lesley Scott, directed by Michael Imison
The TARDIS arrives a space ark, ten million years in the future. The ship is carrying humanity from the doomed Earth to its new home, the planet Refusis Two. Most of the passengers are dormant in miniaturised form; only the essential crew is awake, assisted by the subservient alien Monoids. Dodo suffers from the common cold, and it's soon discovered that neither the future humans nor the Monoids possess an immunity. The Doctor must find a cure before the space ark is ravaged with plague... and, seven hundred years later, confront the terrible consequences as the journey to Refusis Two nears its end.
The Celestial 
Toymaker
The Celestial Toymaker by Brian Hayles, directed by Bill Sellars
The TARDIS is taken to the surreal Celestial Toyroom by the nefarious Toymaker, an old foe of the Doctor's. Steven and Dodo are forced to play a series of games against increasingly deceitful opponents -- dolls and nursery characters, brought to life by the Toymaker -- in order to regain possession of the TARDIS. Meanwhile, the Doctor must solve the Trilogic Game in a battle of wits against the Toymaker himself. If any of the time travellers fail, they will be trapped in the Toyroom forever, transformed into playthings under the Toymaker's control. (Episodes one through three of this story are missing.)
The 
Gunfighters
The Gunfighters by Donald Cotton, directed by Rex Tucker
When the TARDIS materialises in Tombstone, Arizona in the year 1881, the Doctor's first priority is to find help for his toothache. But the local dentist is Doc Holliday, who's being pursued by the Clanton gang for killing their brother. The Clantons' hired gun, Seth Harper, mistakes the Doctor for Holliday, forcing Marshal Wyatt Earp and his kin to intervene. Over the protests of his fiancee, Kate the barmaid, Holliday seizes the opportunity to shake the Clantons; he takes Dodo hostage and prepares to leave town. With a showdown imminent at the OK Corral, who will survive to sing The Ballad Of The Last Chance Saloon?
The 
Savages
The Savages by Ian Stuart Black, directed by Christopher Barry
The TARDIS lands on a planet in the far future, where the Elders live in an advanced city and enjoy a life of peace and prosperity. Jano, the leader of the Elders, knows something of the Doctor's exploits, and invites the time travellers to tour the city. Dodo slips away, and discovers that the Elders thrive because they have harnessed the life energy of the primitive Savages, who dwell in the wasteland beyond the city. The Doctor becomes determined to help the Savages, but he is captured by the Elders. Jano reveals that he intends to harvest the Doctor's life energy for himself... (All four episodes are missing.)
Steven leaves his friends to become the leader of the Elders and the Savages.
The War 
Machines
The War Machines by Ian Stuart Black and Pat Dunlop, directed by Michael Ferguson
Arriving in 1966 London, the Doctor feels that something is wrong in the newly-completed Post Office Tower. He and Dodo learn that it houses WOTAN (Will Operating Thought ANalogue), which is designed to link up with other computers worldwide. But WOTAN has become sentient, and has determined that humanity must be subjugated. WOTAN takes hypnotic control of its creators, and directs them to initiate the construction of armed mobile computers called War Machines. Aware of the threat posed by the time travellers, WOTAN also brainwashes Dodo, with the intention of using her to lure the Doctor into a trap...
Dodo leaves to convalesce; seaman Ben Jackson and his friend Polly board the TARDIS while attempting to return the Doctor's spare key.

Making History

The third season of Doctor Who was a time of disruption. In addition to the upheaval amongst the production team, William Hartnell's health was declining. The arteriosclerosis from which he suffered impacted his ability to memorise lines, and left him physically fatigued. As a result, several episodes were tailored to minimise the Doctor's involvement or eliminate him entirely. Meanwhile, Dalekmania was starting to ebb, and it was clear that Doctor Who could not rely on the Daleks as its sole draw. Lloyd and Davis decided to refocus the series to appeal to a more modern audience, dropping elements seen as old-fashioned. For instance, companions Steven and Dodo were replaced by Ben and Polly, two characters born out of the Swinging Sixties. Similarly, it was decided that modern-day Earth would become a more regular setting, showcasing alien activity in our time rather than confining it exclusively to the far future and other planets.

Season Four (1966): Wearing A Bit Thin

The Stories
The 
Smugglers
The Smugglers by Brian Hayles, directed by Julia Smith
On the Cornish coast in the seventeenth century, the time travellers meet a churchwarden named Longfoot. He claims to be hunted by shipmates from his pirate days, who are determined to recover stolen gold. Longfoot gives them a clue to the location of the treasure, but is murdered by an agent of the vicious Captain Pike. The Doctor is kidnapped by Pike's men, while his companions flee from Squire Edwards, who accuses them of killing Longfoot. Intent on finding the gold themselves, Ben and Polly become involved with Josiah Blake, a revenue officer on the trail of local smugglers. (All four episodes are missing.)
The Tenth 
Planet
The Tenth Planet by Kit Pedler and Gerry Davis, directed by Derek Martinus
The TARDIS lands near an international tracking station in Antarctica. The year is 1986, and the Doctor, Polly and Ben are just in time to witness the arrival in the solar system of Mondas, a planet which is the mirror image of Earth. Soon, Mondas begins to drain Earth of its energy, while the tracking station is invaded by the other world's natives: the Cybermen, humans who have replaced living tissue with cybernetic attachments. Polly and Ben must save their planet and stop the Cybermen from converting all humanity into creatures like themselves... but something is very wrong with the Doctor. (Episode four is missing.)
The increasingly frail Doctor staggers into the TARDIS and regenerates into his second incarnation.

Making History

With William Hartnell's health in decline, the Doctor Who production team made a decision which would -- quite literally -- change the face of the programme forever. Having secured permission to replace Hartnell with a new lead actor, Innes Lloyd and Gerry Davis introduced the concept of regeneration into the series, explaining that the Doctor possessed the ability to change his physical form when his current body had worn out. The result was a “new” Doctor, with a completely different appearance and personality. With this mechanism in place, it was hoped that Doctor Who could survive the departure of its star.