Oxford City Police investigate on the murder of a 15-year-old schoolgirl.

When a secretarial student dies suddenly at home, Endeavour senses that there is more to the case than the initial verdict of heart attack. Now based at Cowley police station, he has become unofficial bagman to DI Thursday but the new superintendent has other ideas. Then a respectable GP is found shot dead in a public lavatory and Endeavour's outlandish theories get him sidelined to general duties.

An unknown menace stalks Oxford, striking fear into the hearts of its citizens. Although the killer appears to be a deranged lunatic, striking at random, Endeavour uncovers an underlying method to the madness. The elaborate staging of the crimes suggests the killer shares Endeavour's passion for opera.

When Princess Margaret unveils the British Imperial Electric Company's new missile, Endeavour is excluded from the event but when a worker is found murdered in a secluded area of the shop floor, he finds himself embroiled in the affairs of the factory and its owners, the Broom family and one of the dead man's colleagues becomes the prime suspect.

When a hit-and-run accident claims the life of an eminent classics professor, events are set in motion which will lead to the Moonlight Rooms nightclub and a blood reckoning. The case is complicated by the appearance of Vic Kasper, DI Fred Thursday's old gangland enemy, whose arrival in Oxford carries a direct threat to all Thursday holds dear.

A baffling suicide, an anguished father searching for his missing daughter, and the robbery of Anglo-Saxon treasures strain even the talents of DC Endeavour Morse, as he returns to the force after a four-month absence from duty.