This follows on, in some respects, from Guards! Guards! The guards have had ethnic equality forced on them, so that they now have some new recruits; a troll, a dwarf and Angua, who is a woman - well sort of. Captain Sam Vimes is getting married, and will be retiring from the night watch, but when he's asked to hand in his badge, he can't bring himself to do so. There's a killer on the loose and he's been told, no, make that ordered, not to pursue this, but the policeman in his soul wont let him do that. The killer has a strange set of victims and it appears to be a very strange weapon, one that has a power all it's own. It was given to the assassins to destory, but it was too powerful for them and then someone stole it... But who? Vimes and Carrot are on the trail, as are the new recruits - all of them!"