Feet of Clay recap

Commander Vimes's City Watch investigates two linked mysteries: a pair of baffling murders of inoffensive old men, and the slow, deliberate poisoning of the Patrician, Lord Vetinari. The city's golems, clay workers owned as tools and driven by the words in their heads, are at the center of it: they had secretly pooled their money to buy and free one of their own and fill it with hopes and instructions, but the weight of conflicting commands and impossible expectations drove that golem mad, and it became the killer before destroying itself. Behind the wider plot stands Dragon King of Arms, the vampire master of the city's heralds, who is poisoning Vetinari and using forged genealogy to try to install a controllable puppet king. Vimes works out that the poison is arsenic soaked into the Patrician's candles. The conspiracy is broken and the College of Arms burns. The golem Dorfl, freed of his owning scroll, chooses to become a moral, self-owning being and joins the Watch, and Vetinari recovers.

Previously, in the City Watch books: Sam Vimes rose from the drunken captain of a near-defunct Night Watch to Commander of a large and growing City Watch, and married the wealthy noblewoman Lady Sybil Ramkin. Under the Patrician, Lord Vetinari, the Watch was rebuilt and opened to the city's many peoples, gaining troll, dwarf, and werewolf officers. Its most beloved member, the giant, dwarf-raised Captain Carrot Ironfoundersson, quietly declined strong evidence that he is the rightful heir to Ankh-Morpork's lost throne, choosing to remain a watchman and to keep the pragmatic Vetinari in power.

Commander Vimes's City Watch, now a large and mixed force, faces two puzzles at once. Harmless old men are turning up murdered with no clear motive, and the Patrician, Lord Vetinari, has begun to sicken in a way his physicians cannot explain and Vimes is convinced is poison. In the background stand the city's golems, silent, tireless clay laborers owned as property, and a new dwarf recruit, Cheery Littlebottom, joins the Watch to help examine the evidence.

Vimes realizes the Patrician is being poisoned not through his food but through the arsenic worked into his candles, and traces the scheme to Dragon King of Arms, the ancient vampire who runs the College of Arms. The old herald has been forging bloodlines to prop up a puppet king and unseat Vetinari, and is entangled with the golems' tragedy. The murders were committed by a golem the city's other golems had secretly bought, freed, and overloaded with words and expectations until it broke; unable to bear what it had done, it destroys itself. Confronted, Dragon King's plot collapses and his heraldic college is consumed by fire. The golem Dorfl, nearly destroyed, has his controlling scroll removed and, rather than falling inert, chooses to keep living and acting by his own conscience; he becomes a free being and the Watch's newest constable. The absurd discovery that Corporal Nobbs holds papers naming him a lost earl is quietly shelved. Vetinari recovers and returns to power, and Cheery Littlebottom is accepted living openly as she wishes.