I listened to the audiobook version of this. I kind of wished I knew this took place in Ancient Rome, as a few months before listening to this I was actually in Rome.
The story is one of my favourites so far in that it uses time travel. Most of the Doctor Who stories have the Doctor arrive somewhere, and then leave at the end, not really using the Timey-Wimey effect. This story has that, and to me, that makes it more interesting. We don't see as much of Ancient Rome as I would like to, but there is a great scene in the Colosseum. The resolution of the problem is well-thought-out, and I was really curious as to how it would turn out. It was rather a surprise, and I'm not surprised easily.
The story is read out by David Tennant. While I've listened to several stories, I have to say, he is my favourite reader. Of course, he has intimate knowledge of the Doctor, but the was he plays with his voice and the different accents is masterful. Makes me want to seek out more of his audiobooks.