Episode 11 of this series of Dr. Who has gone out on BBC1. My word, another corker! If you haven't seen it yet, move on to the next post... Last week's episode, Blink, was brilliant. Genuinely scary in an understated and creepy way. This week's episode bears so much promise.

Professor Yana, from the start, had something 'not right' about him. He could feel the Tardis arrive - and my first thought was 'Master'. Though the hunch was right, I really enjoyed how we got to the conclusion. Professor Yana was played by Derek Jacobi, and was such an amiable character, I knew that he wasn't the Master pretending to be nice, I envisaged his curiosity causing him to look into the Tardis, as Rose did, and somehow becoming corrupted by it. Of course, a more obvious, and more satisfying, solution had been set up, but I overlooked it until I saw the watch at the same time as Martha - the journey in the episode had been so enjoyable that I temporarily forgot about 'The Family of Blood' episodes where the doctor disguises himself.

Derek Jacobi's performance after the transformation was such that I wanted to see him play the master for a while - but it wasn't to be.

His transformation promised bigger treats, with John Simm taking on the Master's role. His entrance as the Doctor's nemesis was superbly pitched - and we're left with a clash of equals.

If the last two episodes (crikey - a three parter! Let's increase that next season, Russell) promise to be as good as the last few, then we're in for a real treat.

I just hope that they don't kill off the John Simm master - let's have some continuity there for a while with a recurring actor. Maybe he could grow a goatee.....?

One disappointment is that in the previews it looks like the Master flees back to 2007 - Martha's mother was in the trailers. In all of Time and Space, please, for the love of all that is good, can't Time Lords stay away from Early 21st Century London? Pretty Please? With any luck, the Master will damage the Tardis' navigation, so the Doctor can no longer control it so precisely (as it should be).

The Good: The Master is Back. Please make it so that he 'gets away' rather than being Vanquished. It's easier to bring him back that way.

Prediction: When the Master hid, his Tardis was never far away, though he couldn't get to it himself - the doctor will find it and give chase.

The Bad: Mad Max wannabes with spikey teeth.

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