The Classic Doctor Who episode Planet of the Daleks began 7 April 1973. It starts with the Doctor (Jon Pertwee) sending a distress signal to the Time Lords after a recent confrontation with The Master. Delirious, he falls into a coma, so the Time Lords control the TARDIS remotely When it lands they find themselves on a strange Jungle planet populated by aggressive and highly poisonous plants who attack Jo as she leaves the TARDIS to explore. The plants also rapidly cover the TARDIS leaving the Doctor in grave danger of suffocation. Jo, in the meantime, discovers a Thal spacecraft in the jungle with a dead pilot. Elsewhere The Thal Spaceship crew includes Taron, Rebec and Codal who find the TARDIS and rescue the nearly asphyxiated Doctor and explain that they are from the planet Skaro. The Doctor learns that his old enemies The Daleks are also on the planet and he is captured and taken to the Dalek base for interrogation.
Meanwhile, Jo is found by an invisible local named Wester who treats her wound and explains that she is on the planet Spiridon and that his people were invaded by the Daleks who released deadly bacteria which killed off most of the population and the remains of his people are trying to fight back against the Daleks, who landed on Spiridon hoping to find out the secret of the Spiridon’s invisibility and reproduce it for their own evil use. He informs Jo that the Doctor and Codal have been captured and taken to the Dalek base. Jo is determined to try to free them.
The Thals meanwhile learn that there is an army of at least 10,000 Daleks in suspended Animation hidden somewhere on Spiridon, so Wester, the Third Doctor, Jo Grant, and the small group of Thals set on a dangerous mission to find the Dalek army and stop it from being revived by sabotaging the Dalek operation. The group find themselves fleeing down the corridors with the Daleks pursuing them while trying to figure out a way to keep the Dalek army from reviving. Elsewhere The Dalek Supreme arrives on Spiridon to oversee the final stages in the revival of the Dalek Army. Meanwhile The Doctor Rebec, Taron and Codal face a race against time trying to stop the Dalek army from being revived.