I suppose that the need during Series A to cram six regulars into each story was a hang-over from “Softly Softly: Task Force”. Of course, in that show the script could just use whichever characters were needed to tell that week’s story – it didn’t matter if PC Snow or DCI Hawkins didn’t appear because they were presumably off duty or on another case. But when it’s just six people living aboard one spaceship, you can’t really do that.
Interesting to read your observations about Zen and Orac. Yes, there is a change in Zen presence by this time that I don’t think I’d realised at the time, and I think you’ve nailed it perfectly.

I remember loving all the material with Tynus in the Avon/Vila narrative – and brilliantly played by Ronald Lacey. In retrospect, I realise how the Blake strand benefits enormously from Paul Daneman as Bellfriar as well.

It’s lovely to see these shows – and particularly episodes like this one which I regard as one of the best – continuing to engage audiences and provide so much enjoyment.

All the best

Andrew