Michaelhouse is inexplicably short of money despite enrolling prosperous students. After the officer responsible for its accounts dies, evidence emerges that the college has paid heavily for goods it never received, raising the possibility of sustained fraud within its own administration.
Matthew Bartholomew is also alarmed by the theft of pennyroyal from his medical supplies and the death of a pregnant woman from an overdose. When her husband proves connected to the missing college funds, financial deception and suspected poisoning converge in an investigation involving inheritance, reputation and the vulnerability of Michaelhouse.