After an encounter with a hostile robot called a Chumblie, the Doctor and his companions are rescued by a group of female Drahvins.

With the knowledge that the planet will be destroyed in two days, the Drahvins instruct the Doctor to help them steal the Rills' ship.

The Doctor and Vicki encounter the Rills and learn the situation is more complex than they thought while Steven finds the Drahvins' hospitality ever more perilous.

The Doctor and Vicki enlist the aid of the Chumblies to rescue Steven from the Drahvins and then find a way off the planet before its destruction.

The TARDIS lands in the middle of the Trojan War, where the Doctor is mistaken for the god Zeus.

While Odysseus forces the Doctor to find a way to win the war, Steven decides to get himself taken prisoner in order to enter Troy and find Vicki and the TARDIS.

With Steven and Vicki being held prisoner by the Trojans, the Doctor's only hope of seeing them again is to suggest the idea of the Trojan Horse.

The Doctor waits inside the Trojan Horse for a chance to reach his companions but Steven's assumed identity as a Greek soldier and Vicki's growing feelings for Troilus endanger their escape.

The Doctor runs afoul of the Daleks and Special Security Agent Bret Vyon on the planet Kembel.

The Doctor infiltrates the Daleks' conference to try and discover their plans, leaving Steven, Katarina and Bret to find a way off the planet.

The Doctor and his friends escape Kembel in the Spar ship but the Daleks force them down on the planet Desperus, where they are threatened by a group of convicts.

With Katarina being held hostage, the Doctor, Steven and Bret are in danger of having to given in to Kirksen's demands, while, on Earth, Chen has them listed as traitors.

The Doctor, Steven and Sara are accidentally transported to the planet Mira where Chen sends the Daleks after them.

The Doctor, Steven and Sara escape Mira in a Dalek pursuit ship but when they find the ship is returning to Kembel, they are forced to come up with a new plan to avoid the Daleks.

The Doctor, Steven and Sara visit a Liverpool police station on Christmas Day and a Hollywood film set during the 1920s.

The Daleks realise the Doctor has given them a fake Taranium Core while, on the planet Tigus, the Doctor encounters the Meddling Monk.

The Doctor, Steven and Sara travel to Ancient Egypt, pursued by both the Daleks and the Meddling Monk.

Steven, Sara and the Monk are captured by the Daleks in order to force the Doctor to hand over the Taranium Core.

The Doctor, Steven and Sara reach Kembel where they find the Daleks have betrayed their allies and imprisoned them.

With the Daleks poised to invade the solar system, the Doctor decides his only option is to activate the Time Destructor prematurely, threatening the entire planet.

The TARDIS lands in sixteenth century Paris and Steven becomes involved with a group of Huguenots.

While trying to find the Doctor, Steven discovers a conspiracy to assassinate a man known as the Sea Beggar.

Steven has discovered the identity of the Sea Beggar, but can he warn the Huguenots in time?

Steven rejoins the Doctor and they leave Paris just ahead of the massacre, leaving Anne behind.

The Doctor, Steven and Dodo arrive on a giant spaceship millions of years in the future, transporting the last humans away from the doomed Earth.

With the Ark infected with a cold virus, the Doctor must convince the Guardians to trust him so he can find a cure.

The Doctor, Steven and Dodo have travelled 700 years into the future and find that the Ark is now under the control of the Monoids as it approaches Refusis.

The Monoids abandon the Ark, leaving Steven and the Guardians to die, but a mutiny in their ranks may give the Doctor a chance to bring about peace.

The Doctor, Steven and Dodo arrive in the realms of the Celestial Toymaker, who forces them to play his deadly games.

While the Doctor continues to play the Trilogic Game with the Toymaker, Steven and Dodo are involved in a deadly game of musical chairs.

Steven and Dodo are forced to cross the dancing floor, where the Toymaker's dolls plan to force them to dance for eternity.

As the Doctor nears the end of his game against the Toymaker, Steven and Dodo take on Cyril in a lethal game of hopscotch to try and recover the TARDIS.

The TARDIS arrives in Tombstone, Arizona in 1891. Where the Doctor is looking for a dentist when he has a toothache, where The Doctor finds the local dentist is the famous Doc Holliday who is in a feud with The Clanton Brothers and their hired gunfighter Johnny Ringo, whilst local sheriff Wyatt Earp is trying to keep the peace. The Doctor, Steven and Dodo find themselves joining forces with The Clanton Brothers and Sheriff Wyatt Earp.

With the Clantons believing the Doctor to be Doc Holliday, Wyatt Earp takes him into protective custody but this leaves Steven and Dodo in danger.

Earp comes to Steven's rescue and arrests Phineas Clanton, prompting the Clantons to decide to enlist the help of Johnny Ringo.

The Clantons have shot Warren Earp, leading to a showdown between the two families with the Doctor powerless to prevent bloodshed.

The Doctor, Steven and Dodo arrive in the far future and are welcomed by the advanced civilisation of the Elders but soon begin to suspect they are hiding a secret.

The Doctor, Steven and Dodo investigate why there are Savages in the Elders' city and uncover the true price of the Elders' perfect society.

The Doctor has been subjected to the Elders' extraction process and Steven and Dodo must return to their city to rescue him.

The Doctor urges the Savages to finally bring an end to the Elders' oppression and enlists the help of an unlikely ally.

The Doctor and Dodo return to London in the present day where the Doctor becomes concerned about WOTAN, a new super-computer installed in the Post Officer Tower.

Dodo is under the control of WOTAN and attempts to lure the Doctor into a trap, while the rest of WOTAN's slaves begin construction on its robotic War Machines.

Ben tries to escape from the warehouse but is captured by Polly, who is now also under WOTAN's control, and forced to work on construction the War Machine.

The first War Machine is defeated but the Doctor only has a matter of hours to destroy WOTAN before the rest of its army is activated.