Robert Amiss is in a mess. He’s left the Civil Service, the bank keeps writing him impertinent letters, and he may soon face the indignity of life on the dole. So when his old friends at the Criminal Investigation Division ask for his help, he is hardly in a position to refuse. The investigation brings him to the Knightsbridge School of English, where strange and disturbing things have been happening. One teacher has met a suspicious death, while another is attacked in what looks like a random mugging. But are the events in fact related? Amiss must become a C.I.D. mole to find out exactly what’s been going on. Unhappily assigned the persona of “Bob”, cad-about-town, Amiss finds himself responsible for escorting a group of obnoxious foreign students while he quietly looks for signs of wrongdoing. He doesn’t have to look for long. A second “accidental” death provides all the proof he needs that something very nasty is in the air and he is quickly drawn into the thick of it.