As volunteers clean up after an outdoor rock concert in Yorkshire in 1969, they discover the body of a young woman, wrapped in a sleeping bag. She has been brutally murdered. The detective assigned to the case, Stanley Chadwick, is a hard-headed, strait-laced veteran of the Second World War. He could not have less in common with - or less regard for - young, disrespectful, long-haired hippies, smoking marijuana and listening to the pulsing sounds of rock and roll. But he has a murder to solve, and it looks as if the victim was somehow associated with up-and-coming psychedelic pastoral band the Mad Hatters. Some forty years later, Inspector Alan Banks is investigating the murder of a freelance music journalist who was working on a feature about the Mad Hatters. Banks must delve into the events of 1969 to find out exactly what hornets' nest the journalist inadvertently stirred up.