When Jack Colby hears the voice of his former wife Eva on the phone he fears the worst – and he is right to do so. The body of her husband, Mexican band leader Carlos, has been found on the towpath of the River Medway and Eva becomes the chief suspect. Car detective Jack goes into action – although he is hindered by a second case, as the beguilingly beautiful twenty-year-old Daisy is determined that his efforts should be devoted to finding her stolen Morris Minor classic known as Melody. Jack storms ahead on both cases but runs into two firstly, the unity presented by the remaining members of the Mexican band Carlos had formed at the May Tree pub twenty years earlier and then abandoned; and secondly, Daisy’s grandmother, Belinda. When a second murder takes place, Jack is right in the centre of the action and the road to its solution means driving headlong into danger.