Who killed Marius Steen, the theatrical tycoon with a fortune to leave his young mistress Jacqui? And who killed Bill Sweet, the shady blackmailer with a supply of compromising photographs? Charles Paris, a middle-aged actor who keeps going on booze and women, takes on detection, by assuming a variety of roles, among them that of a Scotland Yard Detective-Sergeant, and the results are both comic and dramatic. As the mythical McWhirter of the Yard, he actually precipitates the crime; as one of the blackmailer's victims, he finds himself in bed with the blackmailer's wife; as a small-part player in a horror film (The Zombie Walks), he gets shot at by a murderer. And he arrives at the solution by way of the petrol crisis and an abortive attack of the German measles. It's a light-hearted frolic that is, at the same time, a beautifully ingenious puzzle, and it fizzes with fun and wit.