A Sunday Times fiction book of the year'She is an original, with a virtuoso touch' - Hilary Mantel'An extraordinary, quite brilliant book' - C. J. Sansom'A powerful and unsettling novel' - Andrew TaylorThe year is 1793 and Herbert Powyss is set on making his name as a scientist. Determined to study the effects of prolonged solitude on another human being, he advertises for someone willing to live in his cellar for seven years in return for a generous financial reward. The only man to apply is John Warlow, a semi-literate farm labourer with a wife and six children to support. Cut off from nature, Warlow soon begins losing his grip on sanity while, above ground, Powyss rapidly becomes obsessed with Warlow's wife, Hannah. The experiment, a classic Enlightenment exercise gone more than a little mad, will have unforeseen consequences for all included. In this seductive tale of self-delusion and obsession, Alix Nathan has created an utterly transporting historical novel which is both elegant and unforgettably sinister.One of 2019's most high-profile hardback publications, now out in paperback. Featured on Radio Four's Book at BedtimeBBC History Magazine Best Historical Fiction of 2019