This is the first Discworld book I've read since Sir Terry's death. Like the best of his novels, it's a chewy center of humanistic philosophy surrounded by a chocolaty shell of fantasy adventure. The Monks of History have the power to shift time, moving it around to preserve the existence of some kind of timeline. It's vital work, since a mad scientist with a glass clock shattered history once before, and the Auditors, anti-life demons that record all of space and time, are trying to rebuild it and bring about a permanent End of Time. And only Lu-Tze, his apprentice Lobsang Ludd, and Susan granddaughter of DEATH, stand in the way of the apocalypse.

Come for the gentle jokes about kung-fu movies, mountaintop enlightenment, and the Five Horsemen of the apocalyse, stay for the troubles of living in a body, and the basic divide of the dark behind the eyes that is 'Me' and light of the universe in front of it.