It’s the 1970s, and a mysterious woman has a cache of letters to sell. They claim to tell the story of the death of Fanny Imlay, half-sister of Mary Shelley and daughter of Mary Wollstonecraft. Did Fanny really commit suicide in an inn in Swansea in 1816, as historians thought? The letters instead suggest a faked death and an escape from Fanny’s fraught family life. It could have been an independence of which Fanny’s mother would have been proud. But the letters also suggest the re-born Fanny remained misunderstood, mis-used and rejected, in the manner of Mary Shelley’s Frankenstein monster.The women’s intertwining narratives begin to reflect each other as the mysteries multiply and resolve. Gothic body-swaps, dark mansions and unexpected deaths merge with 70s politics and feminism in this tour-de-force by Jerwood Prize-winning author Jo Mazelis.