After the 'Great Stink' of the previous summer when Parliament was overwhelmed by the stench of sewage from the River Thames, and with cholera running rife throughout the city, Charles Dickens has a new enthusiasm. Having formed a firm friendship with Joseph Bazalgette, he is assisting the ambitious young engineer in his efforts to find a solution to London's pollution problem. Dickens' friend and fellow writer Wilkie Collins meanwhile is distracted by thoughts of his pretty new housekeeper and her charming daughter. But what does he really know of his new employee's past - and just who - or what - is making her so frightened? During an exhibition to showcase London's top engineers' plans to solve the sewage issue, proceedings are disrupted by a high-pitched, agonised scream - and the discovery of a blood-soaked body; the result - it would appear - of a terrible accident. Dickens, however, is convinced of foul play, and once again he and Wilkie Collins set about uncovering the shocking truth.