Someone at Oxford's Foreign Examination Syndicate is selling exam secrets. Nicholas Quinn, a member of the board, overhears something he shouldn't know about and is soon found dead at his cottage, poisoned with cyanide - but Nicholas was deaf. Then crossword compiler Philip Ogleby has his skull smashed in. During his investigations, Morse is attracted to Monica Height. She works for the Syndicate and may be mixed up in the corruption which led to Quinn's murder, and perhaps to Ogleby's as well.