They ask only for a pay raise, a new tea kettle and a dartboard.

The Patrician is reinstated as ruler of Ankh-Morpork, and offers the Watch anything they want as a reward. While a crowd attempts to close in on the King to kill it, Sybil tries to plead for it, while Carrot places it under arrest but Errol lets the dragon escape, to be his mate. The Watch's swamp dragon, Errol, reorganises his digestive system to form a supersonic jet engine and fights the king, eventually knocking the king out of the sky with a shock wave. The Librarian helps Vimes to escape and he runs to the aid of Sybil, who has been chosen as the first virgin to be sacrificed. 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 banished dragon returns, and makes itself king of Ankh-Morpork (keeping the head of the Elucidated Brethren as its mouthpiece) and demands that the people of Ankh-Morpork bring it gold and regular virgin sacrifices. The leader of the Elucidated Brethren is initially successful in controlling the dragon, but he has not accounted for the dragon's own abilities. Ramkin gives an underdeveloped dragon, Errol, to the Watch as a mascot. Vimes begins investigating the dragon's appearances, which leads to an acquaintance with Sybil Ramkin, a breeder of swamp dragons. Carrot's enthusiasm strikes a chord with Vimes the Watch should prevent crime, not ignore it. The arrival of Carrot changes this Carrot has memorised the Laws and Ordinances of the Cities of Ankh and Morpork, and on his first day tries to arrest the head of the Thieves' Guild for theft (the Thieves' Guild is permitted a quota of legally licensed thieving, a concept that the book of ancient Laws does not take into account). The Watch is in bad condition they are regarded as a bunch of incompetents who just walk around ringing their bells, and this is mostly true.

It is the task of the Night Watch – Captain Vimes, Sergeant Colon, Corporal Nobbs, and new volunteer Carrot Ironfoundersson – to stop them, with some help from the Librarian of the Unseen University, an orangutan trying to get the stolen book back. Once a suitable state of terror and panic has been created, the Supreme Grand Master proposes to put forth an 'heir' to the throne, who will slay the dragon and rid the city of tyranny. Using a stolen magic book, they summon a dragon to strike fear into the people of Ankh-Morpork. The story follows a plot by a secret brotherhood, the Unique and Supreme Lodge of the Elucidated Brethren of the Ebon Night, to overthrow the Patrician of Ankh-Morpork and install a puppet king, under the control of the Supreme Grand Master (Vetinari's secretary, Lupine Wonse).

Guards! Guards! by Terry Pratchett