Thief of Time by Terry Pratchett

This is one of the best Discworld books. Featuring one of my Favourite characters Lu-Tze the history monk (Extremely under used) He is the mythical Sweeper who follows the Way of Mrs. Cosmopolite, (Which is something of a joke to the senior History monks). He is given as his apprentice the hugely talented Lobsang Ludd (An orphan who was raised by Ankh Morpork Thieves Guild) Together they head out to save the world from the glass clock. Meanwhile Death has tricked his granddaughter Susan into taking action against the Auditors who want to destroy intelligent life in the universe because it is not ordered and upsets their filing