Pratchett is always a good enjoyable read hence the 4 stars rating. Personally, I found this a little too plodding: Sam Vimes comes into contact with another non-human species that has been subjected to prejudice and persecution.... and makes everyone accept them.... And along the way inspires the local cops.

It just didn't quite gel together for me; there was no moment of sublime writing or thought... Jolly good read and enjoyable but not one of his best....