Topher's amazing cat Ka has time-travelled again & left him yet another mysterious clue Following his nose Topher finds himself in Victorian London where disease is rife & the Thames is clogged with stinking sewage! There he discovers a plot to kill Joseph Bazalgette the man who is trying to save the city Determined to foil this foul plan Topher must first escape from an arch-criminal & his den of thieves A thrilling historical fantasy which explores the intriguing hidden details of times past