Guards! Guards! is the 8th book in Terry Pratchett's Discworld series and the third to be featured on the BBC's 100 Greatest Books list. That should tell you something about the quality of writing that appears in the Discworld series. However, since the BBC 100 Greatest Book list is a reader chosen list, this could just mean that he is popular in England, but not really worthy of being placed on the list (I'm looking at you Wilson), however that is not the case. Each of Pratchett's entries into the Discworld series (as of the first eight entries that I have read) have been works of literary art. He crafts language in such a way that many authors try to imitate but never get the full gist of. Of the first eight novels, six have been a standalone stories (Books 1 and 2 form one continuous story-line). However, the way that Pratchett crafts his novels, produces a reading experience that does not force you to read the stories in order. This is also a draw back for the series as well though, where one story does not have many (if any) impact on future stories. Even world altering events, which can occur in one book, are barely referenced, if at all, in future novels. For this reason, the timeline is also very difficult to pin down, even though several characters appear throughout different story-lines within the overall series. The Discworld series broken up into character subsets, where every few books he returns to a character or group of characters (i.e. Rincewind, or the Witches) and focuses on them. And it seems that for the first few books, that kick off stories seem to be his most popular, with all three out of the four Discworld books on the 100 Greatest Books listed being a kickoff story.
Guards! Guards! takes place following the Night Watch of Ankh-Morpork, a group that basically has gone defunct since the Patrician came into power some couple hundred years ago, but the group still persists. The story begins as a sect of people are trying to take over the government by calling a dragon from who-knows-where, to scare the city. This will allow a long lost heir to the throne to come, save the city, and be crowned king, therefore kicking the Patrician out of power. Things obviously don't go as planned and the Night Watch is left to save the day. Out of the three current Discworld stories on the list (that I have read), I would say this one has the most plot, which is definitely a great thing in a book to have. I felt in Pratchett's other books, the story-line could be summed up in just a couple of pages. It was the satire and the way Pratchett describes things though that really made those books worth reading. But with the addition of a worthwhile plot, it elevates this story to one of his better among great stories. His humor, as always, is spot on in this story, with nothing lost through his continuing to write in this series. If anything, his books have become better and better. I would have to say, out of the three books, this book is my second favorite after the first in the series, The Colour of Magic. And that's only because nothing has come close to the humor in that book, of which I don't think he has even tried since. With Pratchett's approach of changing his writing style and character focus through the Discworld series, he has continually made the series feel fresh with each entry. So far, I would say that if for some reason you don't like one book in the Discworld series, try a different book, it is likely going to feel completely different.