Guards! Guards! is the 8th Discworld novel by Terry Pratchett, first published in 1989. It is the first novel about the City Watch.
Warning! Spoilers follow
The story follows a plot by a secret brotherhood, the Unique and Supreme Lodge of the Elucidated Brethren, to overthrow the Patrician and install a king, who would be under their control. Using a stolen magic book, they summon a dragon to strike fear into the people of Ankh-Morpork, so their "heir" to the throne will be accepted. It is the task of the Night Watch, Captain Vimes, Sergeant Colon, Corporal Nobbs, and new volunteer Carrot to stop them, with some help from the librarian of the Unseen University, an orangutan trying to get the stolen book back.
The Watch is in bad condition; they are regarded as a bunch of drunks who just walk around ringing their bells. The arrival of Carrot changes this; Carrot has memorised the laws of Ankh-Morpork, and on his first day tries to arrest the head of the Guild of Thieves for theft. Carrot's enthusiasm rings with the feeling nagging at Captain Vimes; that the Watch should prevent crime. Vimes begins investigating the dragon appearances, which leads to an acquaintance with Sybill Ramkins, a breeder of swamp dragons.
Though the leader of the Elucidated Brethren is initially successful in controlling the dragon; and banishes it when he no longer needs it; he has not counted on the dragon's own magic. The dragon returns, and makes itself king of Ankh-Morpork, keeping the head of the Elucidated Brethren, the now imprisoned Patriarch's secretary, Wonse, as his mouth piece; and demands the people of Ankh-Morpork bring him gold, for his bedding, and regular virgin sacrifices.
Vimes is imprisoned, in the same cell as the Patrician; who has been leading a relatively comfortable life, with the help of the rats he uses as spies. The orangutan helps Vimes to escape; and he runs to the aid of Sybill, who has been chosen as the first virgin to be sacrificed. One of Sybill's dragon's, Errol, fights the king; and wins. While a crowd attempts to close in on the king to kill it, Sybill tries to plead for it, while Carrot places it under arrest; but Errol lets the dragon escape, to be his mate. Synopsis
