Thief of Time is a fantasy novel by British writer Terry Pratchett, the 26th book in his Discworld series. The Auditors hire young clockmaker Jeremy Clockson to build a perfect glass clock, without telling him that this will stop time and thereby eliminate human unpredictability from the universe. Death discovers their plans, but cannot act against them directly, so he instead sends his granddaughter Susan Sto Helit. Meanwhile, Lu-Tze of the History Monks leads gifted young apprentice Lobsang Ludd in a desperate mission.