One thing's for sure, this is a story which could never have been shown as a television episode because it is so dark. There are small things like, some of the characters swear, but the main thing is that the story is very, very creepy. Now, I'm not somebody who's easily scared; I've seen loads of horror films with no effect, but I found much of this to be genuinely creepy and since this is only a book, I consider that a very big achievement! And, as well as spooky ideas, parts of it are downright gruesome...
The Doctor is just fantastic in this too. The Fifth (who is one of my favourites) is known for being one of the most vulnerable Doctors and this book takes his vulnerability really far, I've never seen the Doctor shown in such a weak state anywhere else before, and I love it. Plus, this Doctor is always really nice to people, and, the fact that he keeps up his extreme politeness, even though utterly horrific things are happening all around him, makes him very endearing.
But the Doctor's not the only good character in this. It's very interesting to see how Tegan and Nyssa respond to the situation too, but there are also some very well developed original characters. Cadwell, Stoker and Bunny are all very different people and you'll want to find out what happens to all of them.
You'll notice I haven't said very much about the storyline, or, indeed, what it is that makes the novel so creepy, but I think it's best if you go into it without knowing. There are lots of shocks, twists and turns, making the whole thing a thrilling read. I would, in fact, say that this is the scariest novel I've ever read! Rating: 9.3/10