The finale to the TV Williams Era! And boy, does it go out with a bang! Also, a little Five Doctors moment! I have to say though, I'm not a massive fan of the animation - it does look a bit bizarre, and it's especially jarring when it switches from TV to Animation.

The Fourth Doctor and Romana are having so much fun together - it's nice to see them relaxing on the river, before visiting an old friend. There's still a lot of that Baker magic, possibly for the last time in his run. A particular favourite moment is when he convinces the computer to betray its master - that's so wonderfully Doctory! Douglas Adams just captures the fun and excitement of this Doctor so perfectly, and this is the kind of Romana that I was expecting - fun, strong, independent and a fantastic companion! Thank god this is the last time we see the false K-9. He's used well, but since it's not the real K-9, it doesn't count. In my headcanon, Shada gets interrupted by the Time Scoop from the Five Doctors, and when they return, Romana claims to have heard voices, as a result of the Time Scoop.

The orb effects are pretty good for 1979! Skagra is an odd villain, and I'm not exactly sure who he was, but what he wanted was interesting - an omniscient lifeform to control, studying and stealing the minds of important people - and his main target is Shada! It's an interesting plan, which keeps the audience engaged for six parts, which is impressive - not many stories are able to do that. However, I feel like the way Skagra was defeated was a bit silly and far too easy.

I've already said that the animation was a bit odd, but I think that the ship sets would look so much better animated than in live-action. The location shots for Cambridge look excellent and beautiful, and it's nice to see them realised at long last.

The side characters that we meet over the course of the adventure are original and interesting - a Time Lord living on Earth, teaching at Cambridge - I wonder if this in anyway inspired the Twelfth Doctor to work at St Luke's in Series 10. The two other members of staff at Cambridge are nice additions - they're nothing too special, but they're fun to have around as they get used to life in the TARDIS, and just take it in their stride even though you can tell it's blowing their mind.

The score is reminiscent of City of Death - there's a few variations on that theme, it's nice and jaunty, keeping the tale light-hearted, and at some point in the episode, I think I heard a twist on Big Finish's Fourth Doctor theme - if that was intentional, I applaud them!

This is a great end to the Williams era on TV! I'm not overly fond of everything, but at least it ended on a high! Exciting, fun and wonderfully witty, Douglas Adams shows off everything that made this era what it was! I won't do the comparisons until I finish the fifth season of the Fourth Doctor Adventures on audio, because that's when the Williams era properly ended, and the JNT era began - Ooh, that's going to take a while to get through!