Mary Carpenter (1807-77) was one of mid-Victorian England's most prolific social reformers, starting her career with a focus on the reformation of juvenile offenders. This article considers Carpenter's writings on female convicts in Britain and India and illustrates how her ideas about criminal reformation become discursively connected with a larger project of building a coherent nation as the basis of a powerful empire. Carpenter constructs the bodies of women convicts in Britain and India as a threatening influence on future generations and the Empire as a whole and calls on white middle-class women to reform such 'alien' bodies. The essay explores the intersections of domestic female-led reformism and the imperial project of control over foreign bodies. It demonstrates that imperial history, the history of crime and punishment and gender history must be brought together in order to explore fully the convergence of ideologies of gender, class and racial identity in the mid-Victorian period.