Thousands of men and women all across Britain in the Victorian age were being mesmerized, twisted into bizarre postures and speaking out in unknown languages, and the Victorians were literally entranced with this phenomenon. The text focuses on mesmerism: who was entranced, who did the entrancing, why mesmerism was such a compelling experience to so many and how it became equally powerful evidence of fraud and "unscientific" behaviour to many others. It illuminates dark areas of the relationship between science and society, allowing the assessment of the role of authority in particular social contexts: who draws the line between the bogus and the authentic and how is the boundary maintained? More fundamentally, what is the nature of the powers that wield, and the influences that bind humans together in a social body?