The first half of The Mind of Evil is fantastic, the second half is mostly good. There are three plots which are woven together: the prison and the machine; the missile and the master; then the peace conference. These are very well woven together. The initial theme of mind control as a replacement for capital punishment is an original one. This and the prison setting is surprisingly dark, but perhaps I should stop being surprised at the show's now generally dark tone, its not a children's show any more.

The Master in disguise, then bugging phones and looking suave is fantastic. He so easily could be played in a boorish, pantomime way, but isn't. The performance is masterful. Its a shame that I knew that The Master was in this one before he appeared, it would have been a lovely surprise. On a side note, I love that The Master fixes his TARDIS after only one story, our poor Doctor has been stuck for over a year!

The Master is revealed as being frightened of The Doctor's ridicule. That is a surprisingly profound revelation in only the character's second story, are we meant to draw anything from that? Are his feelings towards The Doctor a contributing factor to his madness?

The Doctor is hilarious in the scene making smart remarks in front of the pompous official. I also loved watching Pertwee wave at the security camera. The casting and acting in the serial is flawless all round. A man who can believably be a thug is then brainwashed and left with the mind of a child, but he manages both roles very well. Captain Chin Lee is a another clear star of this show. The 'Chinese' aspect is slightly overplayed, but as far as 1970s television goes we have seen much worse. Thank God they chose a genuinely Chinese actor to play her, this contributes towards the international feel of this story. Perhaps the most surprising element of Chin Lee's role is that the plot relies on there only being one Chinese girl in the South of England.

The interplay between the different UNIT soldiers is wonderful, it has become a real family. Along with the rest of the family, Jo Grant is excellent, a quintessential Doctor Who companion.

The direction is terrific, the shots of when Chin Lee is about to kill the American ambassador are especially great. The large scale fight scenes in the castle-like prison are fantastic - they look great.

Once the Master loses control of the Keller Machine, I began to disengage with this element of the story to a large extent. The largest fault with this story is that the big baddie for the last few episodes is a prop, not a human or a monster. If this single element was improved, it would be in contention for the best Pertwee story so far. However, the sedate and dull nature of fighting against a prop genuinely damages the story as a whole.

The Doctor saving the world is fairly commonplace in Doctor Who now, they do not shy away from a global story (even if we never see Geneva).