This serial quickly looks like it is going to one of the fairly standard "atypical British colonizers in space resulting in doctor helping primitive, but interesting, culture overcome". Seeing this early on (complete with 'It Ain't 'Alf Hot Mum' characters and even pith helmets), I was pondering on what awful joke I would make in this comment about me "kinda" liking it - and then how I could change that once I understood it was pronounced like the chocolate company. In the end it turns out I didn't need either because this serial is surprisingly strong - and is additionally surprising as it comes off the back of several so-so serial in this new era.
Rather than being simplistic, the story brings in lots of ideas and concepts. We have the standard 'British v natives' but it is subverted with concepts of circular fates and controlling entities. For the practical we have mechanical battle suits to remind us this is sci-fi, mind control, telepathy, and other ideas. All of these work well too - not just thrown at the screen then forgotten. Even the 'villain' of the piece works pretty well in the end, even if the effects have dated. With so many ideas all working, the 4 episodes flew by and felt very satisfying.
It was helped by the sets looking good, but mostly by how good the performances were. Davidson didn't excel but he did his work and was a decent Doctor throughout. Sutton is side-lined for some reason, but her absence helps the plot fee less cluttered (I maintain that 3 assistants is too many), but the downside I saw was that suddenly I've lost the one I like the most. Waterhouse remains limited but he was okay, but Fielding's Tegan was great here. She has a complete side-plot that is intriguing and troubling and she performs all of it really well - much better than the standard 'scream and run' performance. In the guest roles we also have strong turns from Cornes and Sanders, but it is Rouse that really impresses with the range of his character and how much of an impact he makes on the serial at any given point.
Overall a really interesting and engaging serial that has a lot of aspects of strength that add to the whole.