In Settling of the Sun, the tranquil cloisters of an ancient Oxford College become the scene of a gruesome revenge killing. Morse (John Thaw) finds himself in the mystery through the weakness of a pretty face.

A group of overseas students arrive at the college for summer school and Morse is only to happy to oblige when owner of the pretty face, Dr. Jane Robson, played by Anna Calder-Marshall, asks him to attend a welcome dinner to present the winner of a crosswood competition.

During the dinner a Japanese student is brutally murdered- the victim of what appears to be a ritual killing. Or is it?

The main suspects all have a perfect alibi- Morse himself was dining with them when the murder took place. Only Morse can find the real motive.