At the seaside dealing with his late aunt Jane's estate, Scotland Yard Commander Adam Dalgliesh learns that a serial killer, known locally as the Whistler, is on the prowl. The local policeman in charge of the case, Tony Rickards, seeks his advice. He also meets a number of the locals including someone who works at the local nuclear power plant who alludes to safety issues and an anti-nuclear activist who seems bent on raising a ruckus.