Up until this point in the show’s history, there has has only been one other time we’ve had two such strong stories back to back. 1966’s The Tenth Planet into Power of the Daleks, which was 10 months ago in this marathon. Doctor Who is a naturally uneven show, so on the rare occasions that it manages to be consistently flawless I find myself in awe of the producers.

Leela is magnificent. They had a hell of a job following Sarah-Jane but they managed it. Four companion free episodes buttered us up for someone new. Having someone from an entirely different culture who retains some of that culture and does not come across as contemporary the moment they step through the TARDIS doors is also a rarely used and brilliant move at this point. Leela follows in the tradition of several 1960s companions, particularly Victoria, Zoe and Jamie.

The story is of a survey team and a tech team who for generations have been manipulated by a sentient, malfunctioning computer which was set on the wrong course by The Doctor many years before. I mean. Read that pitch. It’s perfect. The survey team becomes the tribe, prized for their brawn and reflexes, the tech team become a learned book smart race. The computer has a plan to use the best example of each species in a eugenics experiment. Bloody hell. Now THAT’S science fiction.

First time Who writer Chris Boucher can stay based on this performance. In fact - he is back next week!