In September 1856 the Chartist leader John Frost, who had been transported for his part in the Newport rising of 1839, returned to Britain from nearly two decades of exile in Van Diemen's Land. Welcomed home by a mass demonstration in London, Frost then embarked on a six-month lecture tour of Britain during which tens of thousands gathered to greet him and to hear him speak on the `horrors of convict life¿. Frost's account was dominated by a tale of brutal tyranny, arbitrary rule and physical torture. It dwelled above all, however, on the alleged bodily degradation and total moral destruction of male convicts, and in particular on the supposed prevalence of `unnatural¿ sexual practices, most notably sodomy, among the men. Frost's lectures have tended to be read by historians as a straightforward, even factual, account of the conditions faced by convicts. This article argues for a more complicated reading, contending that Frost's account of convict life was centrally bound up with a complex of ideas about masculinity and the male body that was integral to nineteenth-century British popular radicalism.