Twin Lakes is a complex of holiday homes in a scenic part of England. “Rest Assured”, says the sign at its entrance. And the people fortunate enough to occupy the luxury homes are indeed able to relax in a beautiful setting. Then a series of mysterious threatening notes are delivered to one of the lakeside homes. DS Bert Hook conducts an informal investigation and the notes cease to appear. All is peaceful once more until a brutal death shatters the peace. As Lambert and Hook investigate the crime, it emerges that the victim was by no means as innocent as most people thought. And it seems that many of the residents have secrets they will do anything to keep concealed…