Matthew Bartholomew returns to Cambridge to find his sister Edith mourning her husband and struggling to control the cloth business he left behind. At the same time, burglaries threaten Michaelhouse, and the rapid construction of the wealthy new Winwick Hall is provoking resentment among older colleges.
The murder of a Guild member is followed by the death of a senior Winwick scholar. As Brother Michael investigates, Bartholomew uncovers rivalry between the university, the town's influential Guild of Saints and the aggressive new foundation, while pressures within his own family make it increasingly difficult to judge whom he can trust.