Written by Terrance Dicks, based on Louis Marks’ scripts for the 1975 TV serial.

This was the second to last story to be adapted from Tom Baker’s second series. Other episodes that year took inspiration from classic horror such as Frankenstein and The Mummy. Planet of Evil has overtones of both the classic ghost stories of M. R. James, such as A Warning to the Curious where a malevolent spirit punishes the amateur archaeologist who steals from the ancient tomb it is guarding, mashed uncomfortably together with a werewolf movie. The result remains, in any format, a perplexing muddle.

The effectively creepy first two episodes, set on the eponymous planet, see the arrogant Professor Sorenson ignoring all the ill omens (such as the death of his entire crew) as he pig-headedly seeks to plunder valuable anti-matter minerals and return them to his home planet to solve an energy crisis. The ghostly sentinel of the planet has other ideas, working its way through Sorenson’s crew to prevent its treasure from being removed.

Most viewers have agreed that the stand-out elements are all contained here, with a hugely impressive alien jungle set and a brilliantly-realised semi-invisible monster. Dicks makes the most of both of these, opening the novel with a description of the planet as “something ancient, alien, hostile to man… The planet was alive – and it was a killer.” And later, “a terrifying quality of otherness” about its guardian

The second half of the story largely switches to the bland corridors of the spaceship sent to rescue Sorenson, which is where things start to fall apart. Under the influence of the anti-matter he has stolen, Sorenson unexpectedly transforms into a wolf-man which is, apparently, allergic to the anti-matter that created him. And then, thanks to the power of neutron acceleration, the wolf-man is replicated multiple times – one senses because that’s the kind of thing the scriptwriter Louis Marks thinks might happen in Doctor Who.

You can almost see Terrance Dicks muttering under his breath as he tries to work this into something that might make sense, while retaining the action of the original script. Impressively, he almost manages it. Thanks to a few scattered paragraphs, he fills in some of the backstory missing from the TV version. We learn Sorenson first learned of anti-matter’s lycanthropic side-effects while on the planet, and has been holding them in check with a hastily-concocted antidote. Elsewhere, Dicks tells us that the files of the Time Lords hold comparable stories of the metamorphic results of anti-matter infection.

Dicks also puts work into the characters, particularly spaceship Controller Salamar. As played on TV by Prentis Hancock, it looks like the Space Service must have been mad to put the unstable Salamar in charge. The adaptation sketches in a plausible backstory, with “highly-placed friends in politics” who have arranged his promotion at too young an age, but have also made sure grizzled old-hand Vishinsky has been installed as a second in command in anticipation of Salamar living down to expectations.

Strangely, it’s the Doctor who seems a little less Tom Bakerish than he should. His slightly Mother Hen attitude to Sarah Jane, as he lectures her “severely”, and his tendency to say things like, “Now look here old chap” to Salamar suggest a slight reversion to the Jon Pertwee version. Grade 4.

Next Time: Doctor Who And… The Mutants.