A short trip set in a really interesting world where it costs money for every word you speak, so only the rich can say what they like. Clearly it's an allegory, but it is handled well, with the Doctor mainly in the background and the focus on a character who is short of cash and so has to choose his words wisely. The choice of the famously talkative 10th Doctor is a good one, as his rambling contrasts sharply to the short, to-the-point, speaking style of the main characters.

It will come as no surprise, given the title, that the story resolves around the desire for free speech, and this aspect of the story works well. There is also a kind of clumsy romance sub-plot which obviously exists to highlight the difference in speech patterns of the wealthy and the poor, but felt unnecessary otherwise. My biggest issue was that the speech patterns of the poor people were not short enough. Several times the main character added an expression, a phrase, or a few extra words which were simply not necessary. A life of counting every word would likely have taught everyone how to say the absolute minimum words in any situation.

Overall, a fun story in a very clever world which made good use of the 10th Doctor and did not include a spurious alien invasion.