In this third volume of the Song Cycle Quartet, Hull private detective Leo Rivers is at the heart of an inquiry into a series of prostitute-linked killings. Approached by the mother of the chief suspect, Rivers quickly understands that this is anything but an open and shut case. Not only is the suspect not involved, but several hitherto unconsidered and scarcely credible connections link the murders to another, as yet unidentified perpetrator. Heading the investigation is an ambitious, career-minded Chief Superintendent, who will stop at nothing to both make a name for himself and to destroy Rivers in the process. Set against the backdrop of the Humber and the long and violent destruction of Hull's once-cherished fishing industry, Swan Song lays bare a world of corruption, exploitation, ambition and of old hatreds and enmities fanned suddenly into destructive life, from which no one, Rivers included, escapes unharmed.