'You can leave a forest, but you can never leave a cloister; you are free in the forest, but you are a slave in the cloister.' Diderot's The Nun (La Religieuse) is the seemingly true story of a young girl forced by her parents to enter a convent and take holy orders. A novel mingling mysticism, madness, sadistic cruelty and nascent sexuality, it gives a scathing insight into the effects of forced vocations and the unnatural life of the convent. A succès de scandale at the end of the eighteenth century, it has attracted and unsettled readers ever since. For Diderot's novel is not simply a story of a young girl with a bad habit; it is also a powerfully emblematic fable about oppression and intolerance. This new translation includes Diderot's all-important prefatory material, which he placed, disconcertingly, at the end of the novel, and which turns what otherwise seems like an exercise in realism into what is now regarded as a masterpiece of proto-modernist fiction.