On the edge of the known universe (Wild Blue Yonder) lies the swamp planet of Zeta Minor. However, the natives are anti-matter monsters that are terrorising the Morestran geological expedition that has landed there and the leader Professor Sorenson has succumbed to the effects of anti-matter. The Fourth Doctor and Sarah-Jane work tirelessly to help the Morestran ship be freed from the planet’s influence so it can escape in one of the most atmospheric Doctor Who stories ever made (thanks to the fantastic film production sets).

Planet of Evil

★★★☆☆

TX: 27/09/1975 – 18/10/1975

Written by Louis Marks    Directed by David Maloney

The Fourth Doctor and Sarah-Jane intercept a distress signal from the planet Zeta Minor at the edge of the known universe. A Morestran geological expedition has fallen prey to an unseen killer and only the leader, Professor Sorenson, has survived. A military mission from Morestra has also arrived to investigate. At first they suspect the Doctor and Sarah Jane of responsibility for the deaths of the expedition members, but the culprit is eventually revealed to be a creature from a universe of anti-matter, retaliating for the removal by Sorenson of some anti-matter samples from around the pit that acts as an interface between the two universes. The Doctor falls into a pit that takes him into the void between both universes (The Three Doctors, The Impossible Planet/The Satan Pit, Army of Ghosts/Doomsday, The Well). The Morestrans take off in their ship, but it is slowly dragged back towards the planet due to the anti-matter on board. Sorenson himself becomes infected by anti-matter and gradually transforms into an ‘anti-man’, a monster capable of draining the life from others. Sorenson’s eyes turn red like the Ood (The Impossible Planet/The Satan Pit, Planet of the Ood). This story is a pastiche of Dr Jekyll and Mr Hyde. The Phillip Hinchcliffe/Robert Holmes era of Doctor Who borrowed heavily from the hammer horror genre, which led to the creation of many classic stories in the early Tom Baker years. The Morestran commander, the increasingly unhinged Salamar, attacks Sorenson with a radiation source, but this only causes him to produce multiple anti-matter versions of Sorenson which soon overrun the ship. The Doctor finds the original Sorenson, takes him back to the planet in the TARDIS and throws both him and his samples into the pit, fulfilling a bargain he earlier made with the anti-matter creature. Sorenson reappears unharmed, and the Doctor returns him to the Morestran ship, which is now freed of the planet’s influence.