Leaving his grandchildren in the TARDIS, the Doctor explores a volcano. He soon discovers that the volcano is in fact a secret base from which an evil master mind intends to dominate the Universe. The Doctor attempts to thwart the plan depositing the villain's deadly missiles in the heart of the volcano where they explode.

The Doctor pilots the TARDIS to the planet Trodos where he intends to make peace with his old enemies, the Trods. However, on arrival the Doctor finds that his intentions have been anticipated by the Daleks who have massacred the Trods. The Doctor, John and Gillian soon make contact with the surviving Trods whom they join forces with to defeat the Daleks.

Determined to take his revenge against the Daleks, the Doctor constructs a "home made" Dalek in which he intends to infiltrate a Dalek garrison. Once within Dalek ranks, the Doctor discovers that the Dalek Supreme is planning to produce many more Daleks to invade the rest of the Universe. However, the Doctor cannot act on his new found knowledge before his charade is discovered.

The malfunctioning TARDIS lands in London, 1969, where the Doctor discovers that Earth's inhabitants are under the hypnotic control of the alien Zagbors. Trapped in the immobile TARDIS and bombarded by the Zagbors high-powered ray cutters, The Doctor has no choice but to surrender to the aliens.

Landing on a sinister jungle planet, the Doctor tests out his new "ray gun" weapon. The Doctor and his grandchildren soon find themselves being pursued by a giant metal spider. Within the spider is an evil genius who is able to control a group of real giant spiders wit ultrasonic sound. In a bid to return to the TARDIS, the Doctor attempts to turn the tables on the villain by using his recorder to control the spiders' action.

The Doctor, John and Gillian discover that the Daleks have constructed a giant exterminator which they are intending to use o destroy the Earth with one devastating blast. After derailing the Dalek express train that carries the weapon's operating crew, the Doctor must ensure that the giant exterminator will never been used by the Daleks.

Landing in New York of the Sixties, the Doctor, John and Gillian are confronted by dinosaurs that have been revived by a mad scientist and his "life drug". The Doctor manages to concoct and "antidote" that will reverse the effects bu he must find a way to administer the drug to achieve victory.

The TARDIS lands in the village of a jungle tribe who worship it as their new idol. The Doctor decides to use "space-age thinking" to help the natives defend themselves from their enemies.

The TARDIS lands on the planet Verno after its robot forces have been defeated in a space war with Earth. However, beneath the surface, the exiled Arborge Quince is manufacturing more robots. It is up to the Doctor and his companions to prevent another war...

Landing in Egypt, 1880, the Doctor finds himself in the middle of the conflict between the British and Mahadi's tribesmen. Disguised as one of the tribesmen, the Doctor makes contact with General Harvey's forces to warn them of an imminent attack. However, the Doctor is accused of being a spy and, his warnings ignored, is thrown into gaol.

The Doctor investigates a damaged spacecraft on the planet Minot not realising that the vessel belongs to the Cybermen. When the Cybermen return to repair their ship, the Doctor is trapped on board when it takes off. The Doctor discovers a giant bomb on the cyber-ship that the Cybermen intent to use to destroy the Earth. Priming the bomb to detonate, the Doctor has twenty five minutes to escape before the cyber-ship is blown to pieces!

Landing at an American air base in the Arizona desert in 1988, the Doctor investigates the mysterious destruction of several jet planes whilst on their test flights. The Doctor pilots a jet himself and only escapes from a crash-dive by using his own rocket pack. The Doctor is captured by an enemy power hiding in caves below the desert. By operating a magnetic device they are causing the American jets to crash. The Doctor must warn the air base and escape with only his rocket pack to help him.

The TARDIS lands on a planet swarming with butterflies and moths. The Doctor, John and Gillian meet eccentric insect collector Professor Gnat who, despite the Doctor's warnings, is captured by the Cybermen. Discovering several dead Cybermats, the Doctor realises that the scent of the planet's flowers is deadly to the Cybermen. Armed with bunches of flowers, the Doctor and his companions venture into the Cybermen's underground city to rescue Professor Gnat.

On the planet Vargo the Doctor and his companions come across a gathering of witches from throughout the universe. Using a variety of gadgets from his utility belt, the Doctor is able to scare off most of the witches by convincing them that he is the powerful Wizard Omega. However, the Grand Witch sees through the Doctor's ruse and schemes to take her revenge on him.

In 1870, the Cybermen land a giant cyber-mole vehicle just outside London. Using the mole, they burrow deep into the Earth below the capital and steel the doomsday deadly bomb from its vault. With the bomb in their possession, the Cybermen hold the world to ransom. The Doctor's knowledge and experience are welcomed by the helpless military and armed with anti-Cyberman weapons, the Doctor leads an assault on the cyber-mole.

The Doctor, John and Gillian land on a beautiful planet but are soon menaced by savage, sabre tooth gorillas. Escaping from the beasts the Doctor and his companions meet a professor who has developed Squidge, a fantastic new substance. Attacked once again by the gorillas, the Doctor has only the elastic properties of Squidge to help them all escape.

Landing on a planet, the Doctor, John and Gillian discover the Cybermen are using slave work force of Earthmen to construct a giant city in honour of their Controller. Disguising himself as a slave, the Doctor hatches a plan to free the oppressed work force.

On a volcanic planet, the Doctor and his travelling companions encounter a group of shipwrecked school children who are being menaced by a race of hideous land squids called Dyrons. The Doctor attempts to make use of the planet's natural instability to eliminate the threat of the carnivorous Dyrons.

The Doctor offers his services to Zarcus, leader of the peace loving planet of Neon. Ships carrying Neon's food supplies from it's neighbouring planet, Barren are being attacked and boarded by space pirates. The Doctor offers to take a ship and to collect the food from Barren. However, on the return journey, the Doctor and his companions are attacked and captured by the pirates and are sentenced to walk the plank.

In 1989 on the planet Velon, the Doctor designs a revolutionary new car that is indestructible. The car is soon stolen, however, by an evil criminal who use it to commit a smash-and-grab robbery on a truck transporting gold bullion. It is up to the Doctor to prevent the unscrupulous villain from using his invention to commit more crimes.

Landing on the planet Comedy, the Doctor, John and Gillian are set upon by the alien Jokers who terrorise the travellers for their own amusement.

After being warned of imminent danger by a fortune teller, the Doctor parts company with John and Gillian, enrolling them in the university on the planet Zebadee. Landing in a Scottish castle the Doctor encounters the spear-head for a Quark invasion. Reunited with his old companion, Jamie McCrimmon, the Doctor does battle with the evil robots in an attempt to thwart their invasion of Earth.

On the war-battered planet of Gano, the Doctor and Jamie are set upon by giant wasps sent by their enemy, the Quarks. The two travellers take refuge in an underground city but are horrified to discover the Quarks themselves are waiting for them.

Alien invaders land near Earth's South Pole in 1970. Threatening to blow the world off its axis unless the people of Earth capitulate to their will, the aliens demonstrate their power with a huge explosion. The Doctor and Jamie encounter a savage race of Ice Apes who have been set free by the aliens' detonation.

Landing on a jungle world, the Doctor and Jamie are horrified when a Quark ship causes the TARDIS to be buried under rubble. Pursued by their robotic enemies, the travellers make use of a giant tractor to turn and fight their enemy.

The TARDIS lands in the temple of time which is full of giant clocks. The Doctor and Jamie meet Father Time who flies into a rage when he discovers that his two visitors travel through time. Determined to put the Doctor and Jamie to death for their "evil excursions", father Time consigns Jamie to die in the falling sands of a giant hour glass and the Doctor to be lowered by pendulum into a vat of boiling oil.

The Doctor invents Martha, a robot which is designed to do housework of all kinds. Landing in the New York of 1971, the Doctor takes his invention to International Inventions who mass produce the robots in their millions. Watching this are the Quarks who transmit a signal which causes the Marthas to turn on humanity. With America weakened, the Quarks launch their invasion.

The Doctor lands the TARDIS on the planet Hekton in 2044. The planet has been colonised by humans who have adopted the lives of Regency gentry. The Doctor is taken prisoner and used as sport but a murder squad of Quarks soon arrive intent on eliminating the time traveller. Eventually all but one of the Quarks are defeated by the gentry and the Doctor has to face the remaining robot in contest.

Landing on an ice planet the Doctor decides to partake in a spot of skiing. However, he is soon horrified to discover a patrol of Cybermen. Faking his own death to put the Cybermen off his scent, the Doctor joins forces with Joe, a native Eskimo. Armed only with Joe's robot gulls and a basket of exploding eggs, the Doctor and Joe attack the Cyber encampment.

The TARDIS lands on the sea of the planet Nook. Sinking beneath the waves, the Doctor dons a divers suit and goes for a walk on the sea bed. Discovering a crashed spaceship, the Doctor attempts to help the crew to repair and relaunch their vessel. However, his efforts are hampered by a giant squid.

Materialising on a jungle planet, the Doctor discovers Jason Wurlitzer who is being held captive by a race of hideous dwarfs. The Doctor is also captured and then dispatched with a ransom message to Jason's rich father, Kurt. However, Wurlitzer Snr. refuses to hand over the uranium requested by the Dwarfs. Instead he asks the Doctor to assemble a crack team and head a mission to rescue Jason.

At his London hotel, the Doctor comes across three young brothers who decide to rebel against their guardian, Mr Fitz-Walker. Despite the Doctor's pleas, the youngsters flee from the hotel and steal Fitz-walker's private jet. However, unknown to them, the jet was to be used as a getaway plane by Fitz-walker's men who are busy stealing weapons secrets from a nearby nuclear arsenal.

The Doctor is cooperating with a team of scientists who want to examine him and learn about the effects of time travel on his body. Carthwright, one of the scientists, falls into a coma at the sight of a strange mark on the Doctor's chest. The Doctor tells the other scientists that it is the Marck of the Blenhim, a race of evil warmongers who ravaged the galaxy. The Doctor realises that Cartwright must be a descendent of one of the refugee Blenhim victims and attempt to shock him back to consciousness by recounting his own battle with the Blenhim Master Race.

Abducted from his hotel by a Mafia-like group known as the Brotherhood, the Doctor is forced to develop an explosive which will release an Aztec treasure hoard from a Mexican lake-bed. Once in Mexico, the explosives appears to do its job until hoards of giant prehistoric worms threaten the Doctor and the villains.

A young boy called 'Specs' receives an SOS from an orbiting Quotron space craft. When the Doctor hears the signal he contacts the Quotrons and arranges a rendezvous with them in the Arizona desert where he repairs their faulty navigation equipment. Unfortunately, the Quotron leader is unwilling to allow knowledge of their visit to earth to become common knowledge and intends taking the Doctor and 'Specs' with them when they leave.

Appearing on the TV panel game show Explain My Mystery the Doctor becomes intrigued by the story of walking scarecrows told by farmer Glenlock-Hogan. Investigating further, the Doctor discovers the tale to be true and he is further shocked when the scarecrows call his name. They have been animated by the Time Lords to carry out the remains of the Doctors' sentence by investigating his change of appearance.

The Doctor invents a labour-saving robot, which he names Barnabus. However, when the TARDIS lands on a planet, the inhabitants see Barnabus and assume that the travellers' intentions are hostile. The TARDIS crew takes cover from the inhabitants' gun fire and it is up to Barnabus to save the day.

The Doctor and his companions are testing a new "exploration truck" on a jungle planet when they are attacked by the Daleks. With the truck destroyed the travellers attempt to escape by swinging Tarzan style through the jungle on creepers.

While testing a new travel 'bug' on a swamp planet, the Doctor, John and Gillian once again encounter the Witches. Intent on thwarting the Witches' plans to conquer the Earth, the Doctor attempts to convince the old hags that his 'bug' is a swamp demon.

John and Gillian are captured by Cybermen and imprisoned in a cyber outpost. Ina n attempt to infiltrate the outpost and rescue the children, the Doctor disguises himself as Cyberman.

When the TARDIS is caught in a web the Doctor is captured and forced to take part in a wrestling match while spectators look on. After defeating his giant ape-like opponent the Doctor is named as champion. However, he is then forced into a contest with a Cyberman.

The TARDIS materialises in a magnificent city owned by Heinrich Karl, the wealthiest man in the Universe. The bored Karl use the Doctor to amuse him in his attempts to escape.

Whilst testing out the Doctor's new pedal-copter, the three travellers are attacked by a group of Daleks. With the pedal-copter destroyed, the Doctor, John and Gillian have no option but to confront the Daleks if they are to return to the TARDIS.

With the Trods own time-ship in hot pursuit of the TARDIS, the Doctor lands his Ship on prehistoric Earth. The Doctor, John and Gillian are delighted to discover a herd of woolly mammoths who become friendly when the Doctor plays his recorder. Shortly after discovering the location of the Trod vessel, the Doctor is captured by his old enemies who intend to kill him with the deadly rays of an atomiser!

In a museum in a ruined city, the Doctor, John and Gillian do battle with a group of Cybermen. To evade the Cybermen, the travellers make use of the various exhibit on display.

In 2208, the Doctor and his companions ingratiate themselves with a pop group called The Electrodes. The Doctor accepts the group's offer of becoming their manager. However, he has to contend with his predecessor who intends to take his revenge on the group by blowing them up on stage.

The TARDIS lands on Earth in the year 2053 and the Doctor finds himself a driver in a veteran car race. However, the Doctor finds that he is being chased by a Quark who has hijacked a motorway patrol vehicle and is intent on destroying him.

The Doctor joins a group of scientists to witness the test run of a new fighter plane called the Dart. The observation plane carrying the Doctor and the scientists is hijacked by a group of Cybermen. With no other option the Doctor escapes to the experimental Dart, intent on using it against his old foes.