One resource is time. It must be managed, as everyone is aware. You can allow it to travel quickly or slowly, but you cannot let it come to a complete halt. The History Monks are charged with the critical task of making sure that tomorrow always comes on the Discworld. But a race against time begins with the creation of the first fully accurate clock. The clockmaker must be stopped before he finishes his work, and Monk Lu-Tze, his apprentice Lobsang Ludd, and Death's granddaughter Susan must help. Because a clock that is truly precise will stop time entirely. Then there will indeed be no tomorrow.