When the head of the local cop shop phones to call in a favour, our PI is unable to refuse.Electricity magnate, Theo Carr wants to know what his son is up to. All the Gumshoe has to go on is a scrap of paper and two words. Soliciting the help of his old friend Jimmy the Griff leads the PI to young Donny Carr and a syren club. A syren song can turn your brain to mush. Donny is syren-smitten.But just why is Captain Silverback so interested? What links Carr's electricity empire to the syren clubs? Fortunately, Gumshoe has wax earplugs and an operatic skeleton key to help him solve the case.