Who's murdering harmless old men? Who's poisoning the Patrician?
As autumn fogs hold Ankh-Morpork in their grip, the City Watch have to track down a murderer who can't be seen. Maybe the golems know something - but the solemn men of clay, who work all day and night and are never any trouble to anyone, have started to commit suicide...
It's not as if the Watch hasn't got problems of its own. There's a werewolf suffering from Pre-Lunar Tension. Corporal Nobbs is hobnobbing with the nobs, and there's something really strange about the new dwarf recruit, especially his earrings and eyeshadow. Who can you trust when there are mobs on the streets and plotters in the dark and all the clues point the wrong way?
In the gloom of the night, Watch Commander Sir Samuel Vimes finds that the truth might not be out there at all.