The Auditors convince a young clock maker, Jeremy Clockson, in Ankh-Morpork to build a perfect glass clock. They do not reveal that this will imprison Time (the anthropomorphic personification) and thereby freeze time (the physical quantity) on the Discworld. Naturally, Death isn't about to let that happen, but since his hands are tied he sends his granddaughter Susan to thwart them.  Meanwhile, in a distant valley, a young apprentice of the History Monks, Lobsang Ludd, and his old teacher, Lu-Tze, called 'The Sweeper', hear that a glass clock is being built. Lu-Tze knows of such a clock's side-effects, since he was sent to prevent a previous clock from being built. He and Lobsang head for Ankh-Morpork to stop Clockson from building it.  The Auditors, meanwhile, are using human bodies to pose as and learn about humans. One in particular, operating under the alias Myria LeJean, is quite disturbed by "her" experiences as "she" becomes more and more human by the minute...

A really good and interesting book. The 5th Beatle parody was exceptionally witty and the History monks was interesting too. The idea of Time having two sons (or in this case the same son twice) is really cool and as this is not revealed immediatley it keeps you guessing through the book which is which and then it turns out they both are. The Auditors have become a little bit tiresome, for me at least, but they get a fresh spin put upon them in this story and I really hope its the last time we encounter them. Susan's also showing more and more signs that she's becoming like her mother, in this case though she takes death by chocolate to a whole new and unexpected level!