Captain Sam Vimes' life in the City Watch is changed forever when a figure from his past returns to Ankh-Morpork.

The Watch connect Carcer's evil plot to strange proceedings at the magical Unseen University, using Constable Carrot's policing know-how.

The Watch must break into the city's most secretive and dangerous institution in a desperate effort to find the magical artefact known as Gawain.

Carcer is willing to do anything to find the sword for Gawain; the Watch follow close on his tail to the Twilight Canyons, a place where elderly residents await death.

Captain Sam Vimes sets off through the Unreal Estate to destroy the sword in a magical lake, with thieves hot on his trail.

In the race against Carcer for the second mystical artefact, Cheery, Angua, and Carrot enter the Mines of Tak; Cheery confronts the darkness in her past; Vimes and Sybil defend the besieged Watch House from Doctor Cruces and her Assassins.