The High Priest of In was inspired by a very vague recollection of a book I read when I was in junior school, called The Secret Mountain by Enid Blyton. It was a strange little tale involving well mannered English children and an African tribe who lived in a mountain and liked to sacrifice people. Mary Whitehouse was obviously too busy criticising Doctor Who to worry about what we were READING in the 1970s! Anyway, the idea of a mountain, primitive people and sacrifices stuck in my mind. The other thing that stuck in my mind about the Blyton story was the fact that a total eclipse of the sun was a major plot device, and I really would have liked to have used that, but an eclipse was also used in the Doctor Who adventure, The Aztecs in 1964. That story also involved throwing people off high places, so I really wanted to make sure I didn’t too obviously clash there. Reluctantly I had to lose the eclipse device.

The mountain looking a bit like Uluru, is of course because Uluru is the only mountain rising up from a plain I actually know of. There may well be some in Africa, but I’m not sure about them. Donna not remembering the Aboriginal name of the mountain is, I think, pretty much normal for British people. Even I had to look it up on Google as I couldn’t remember how to spell it. Actually, I spelt Ayers Rock wrong, too. For some reason I thought it was spelt Ayres. But I got there in the end.

The In-Wer, half elephant, half camel, and the fantastic vegetation that appeared after one shower of rain was thought up in my half sleep while I was still planning what else would happen. I wanted to get away from dry plains while still setting the mountain on a dry plain. They all went towards making the scene much more exotic and alien. They also provide a major plot device when the In-Wer stampede and knock the TARDIS over. Now, I don’t actually think the light on top has anything to do with the translation system. TARDISes aren’t all police boxes after all. But the fact that there is some damage to the TARDIS allows for the issue with languages that is central to the introduction of the In-V’il and their high priest.

Originally there was going to be a more straightforward story about primitives and their sacrifices. At some point after I started writing, though, I thought of having the High Priest turn out to be a traveller from elsewhere who had taken to the lifestyle. THEN I decided he might actually be the Time Lord who had written about the planet and drawn The Doctor to it. This made for a rather more interesting and different story and got right away from both Secret Mountain and the Aztecs. It then became a meeting of Time Lord minds and a question of trust, and The Doctor eventually saving Kocieda’s life despite his initial hostility.

Of course, this means another Gallifreyan alive in the universe despite the belief that all the Time Lords except The Doctor are dead. But since Kocieda isn’t living as a Time Lord he doesn’t count. Thank you, Russell T. Davies for the invention of the Chameleon Arch device. Used sparingly, it is a brilliantly useful plot device.