Four to Doomsday
Four to Doomsday was the second story in the nineteenth season of Doctor Who. It was the first story filmed with Peter Davison as the Fifth Doctor.
The Doctor tries to return Tegan to Heathrow Airport, but the TARDIS lands on a technologically advanced ship. The Doctor goes out to investigate and sees a monoptican surveying them. He returns to the TARDIS and emerges with Adric, Nyssa and Tegan. All four must wear helmets to breathe. The Doctor addresses the monoptican, hoping whoever is using it for surveillance will see they are friendly. He queries it on their location. A door opens. Seeing this as a friendly gesture, the Doctor goes through it, followed by Tegan..
Nyssa and Adric stay in the room to operate some machinery there. Tegan and the Doctor eventually find themselves on the ship’s bridge and meet the Monarch and his two associates, Enlightenment and Persuasion. The Monarch is interested in the Doctor and Tegan’s knowledge of current and past Earth culture. He reveals the ship is bound for Earth. Tegan draws a picture of male and female uniforms at Heathrow for Enlightenment. Tegan and the Doctor leave the bridge and meet up with Nyssa and Adric.
Nyssa claims she saw a humanoid man. The Doctor doubts this until one emerges, dressed in a Greek toga, to ask them to follow him. They are led to a dining chamber and seated at a table, to be joined by an Aborigine(Kurkutji), a Mayan (Villagra) and a Chinese mandarin (Lin Futu). They are representatives of their respective cultures; the Greek (Bigon) represents ancient Greece. The last guests to join them are Enlightenment and Persuasion, who have transformed into the humans Tegan sketched.
The TARDIS crew are reunited as guests aboard the ship. It soon becomes apparent there are four distinct human cultures represented by a small group of humans: Ancient Greeks, the leader of whom is the philosopher Bigon; Chinese Mandarins and their leader Lin Futu; Princess Villagra and representatives of the Mayan people; and Kurkutji and his tribesmen, of the Australian Aboriginal culture. The Urbankans have visited Earth, each time getting speedier in their journeys.
This time they have left their home world after erratic solar activity, storing three billion of their species on slides aboard their craft. It seems the current journey is their last and they wish to settle on Earth, which they are due to reach in four days. Bigon demonstrates to an astonished Doctor that within his chest and beneath his face there is just a mass of electronics. Holding up a printed circuit connected to his chest, he states: “This is me…”
The Doctor becomes suspicious of the Monarch. He learns the Urbankans don’t plan on a peaceful co-existence with humans. Instead, they will use a toxin that the Urbankans produced from their own bodies during the “flesh time” before they were converted to androids, which causes organic matter to shrink away to nothing. It will be unleashed before the Urbankans disembark.
The Doctor discovers the humans aboard are not descendants of the original abductees. The original people were taken from Earth and converted into androids, just like the three Urbankans. This revelation causes a panicked Tegan to use a spare key to get into the TARDIS, and she tries to pilot it back to Earth, but only succeeds in materializing it space next to Monarch’s ship.
The four leaders have been given additional circuits to help them reason, but this faculty can be taken away, as Bigon learns when he crosses Monarch once too often.
He explained to the Doctor that Monarch strip-mined and destroyed Urbanka in a quest for minerals to improve the ship, and now plans to do the same to Earth. Monarch believes that if he can move the ship faster than the speed of light, he can pilot it back to the beginning of time and discover himself as God. Adric is restrained as, on Persuasion’s orders, the Doctor is forced to his knees and one of the Greek androids raises a sword to decapitate him…
Nyssa uses the Doctor’s sonic screwdriver and a pencil to short out the androids and save his life. Adric stops Persuasion from shooting the Doctor by standing in the way and the Monarch announces the Doctor is not to be harmed. Despite these events, Adric is taken with Monarch, and relations between the Doctor and him become very strained. It takes the truth to break the alien’s hold over the boy.
The Doctor sets about overthrowing Monarch and, with the help of the human androids led by a restored Bigon, a revolution begins. The Doctor is forced to go out into space in order to retrieve the TARDIS, but Persuasion and then Enlightenment attempt to stop him; the Doctor and Adric tear out their circuits and throw them into space, before the Doctor is able to get back into the TARDIS and return to the ship. Monarch tries to kill the TARDIS travelers by shutting down life support, but they are able to survive with the help of the helmets they brought from the TARDIS.
The Doctor retrieves a sample of the Urbankan toxin, intending to analyse it and turn it against its creator, but when an armed Monarch confronts the Doctor, he’s forced to use the entire sample against Monarch, who is reduced to just inches tall. It seems he is a product of the weak “flesh time” after all, having never, as the Doctor suspected, been fully converted into an android. Adding insult to injury, the Doctor reveals that Monarch’s plan to travel back in time was ridiculous, and would never have worked.
With their former ruler now captive and helpless, the humanoid androids decide to pilot the vessel to a new home on a new world, while the TARDIS crew departs. Back in the console room, Nyssa collapses to the floor in a dead faint…