Felix McClure, a professor at Oxford University, was stabbed to death during his university study. He is not only an expert in this field, but also one of the main fund-raisers of the university. The focus of the investigation is Brooks, a former cleaner of McLure, who suddenly quit his university job after a student Matthew Rodway jumped out of a building because of drug abuse. When Morse learned that Brooks' daughter was the object of love of Rodway and another student, he had another possible suspect. Brooks' wife also works for a friend of McLure, and Morse exposes a conspiracy that he may not be able to prove.