Making money : a novel of Discworld / Terry Pratchett.

Enhanced descriptions from Syndetics:

"Outlandish fun. . . . Making Money balances satire, knockabout farce and close observation of human -- and non-human -- foibles with impressive dexterity and deceptive ease. The result is another ingenious entertainment from the preeminent comic fantasist of our time." -- Washington Post

The hero of Going Postal returns in the 36th installment of Sir Terry Pratchett's beloved Discworld series! Moist von Lipwig, condemned prisoner turned postal worker extraordinaire, is now in charge of a different branch of the government: overseeing the printing of Ankh-Morpork's first paper currency.

Amazingly, former arch-swindler-turned-Postmaster General Moist von Lipwig has somehow managed to get the woefully inefficient Ankh-Morpork Post Office running like . . . well, not like a government office at all. Now the supreme despot Lord Vetinari is asking Moist if he'd like to make some real money. Vetinari wants Moist to resuscitate the venerable Royal Mint--so that perhaps it will no longer cost considerably more than a penny to make a penny.

Moist doesn't want the job. However, a request from Ankh-Morpork's current ruling tyrant isn't a "request" per se, more like a "once-in-a-lifetime-offer-you-can-certainly-refuse-if-you-feel-you've-lived-quite-long-enough." So Moist will just have to learn to deal with elderly Royal Bank chairman Topsy (née Turvy) Lavish and her two loaded crossbows, a face-lapping Mint manager, and a chief clerk who's probably a vampire. But he'll soon be making lethal enemies as well as money, especially if he can't figure out where all the gold has gone.

The Discworld novels can be read in any order, but Making Money is the second book in the Moist von Lipwig series.