1)You know, people complain about Tegan, but I find Peri more irritating,
2)We finally get an explanation for the celery. Kind of a lame explanation, but an explanation, nonetheless. "I'm allergic to certain gases in the Praxis Spectrum" and "It's a powerful resotrative where I come from." (They have celery on Gallifrey?)
3)I don't know, I didn't think the magma-monster was all that bad. Not all that good, either, I suppose.
4)John Normingtom was quite good as Morgus. I got a sort of "younger Montgomery Burns" vibe off of him.
5)Christopher Gable did OK as Sharaz Jek, another Holmesian deformed, masked weirdo who lives in a hole. He also gets to be the first villain to lust after Peri. He does get a good death scene: "You think bullets could stop me now?"
6)Maurice Roeves was also good as the casually brutal Stotz.
7)Lots of violence in this - both seen and implied. I gather the fact that people in the future are still using bullets rather than rayguns was a deliberate choice by Graeme Harper to make the violence more "real".
8)Jek sure got those android replicas of the Doctor and Peri ready pretty fast, didn't he?
9)"It could have been worse." "In what way, Trau Morgus?" "It could have been me."
10)I hadn't really noticed this the first time I watched this, but the "regeneration effect" starts briefly in Part Three, like he's fighting it off. It might've bene interesting to have him change in the middle of a story, once.
11)"Hello, Doctor." "That's more like it." "Goodbye, Doctor."
12)I thought the regeneration scene was well-done, with the montage of the companions and the Master. Interesting that the Fifth Doctor's last word was "Adric". On the commentary, Davison complains - humorously - that the viewers would be distracted from his acting by the fact that the camera seems to be focused on Nicola Bryant's cleavage.
13)And the Sixth Doctor's first words are: "You were expecting someone else?"
14)Also interesting that all of the male characters die - even the Doctor, sort of - and only Peri and Timmin come through intact.
Davsion has said that he made the decision to leave at the start of his third season, and that if there had been more stories like this one in his second season, he might have decided to stay longer. For me, this is the last really good story that Holmes did for the show, and a good one for Davison to go out on. Also the directorial debut of Graeme Harper on the show, and I think he did a good job of it - I found this quite a tense, excting story.
[Part of list of Doctor Who episodes here.]