'A wonderful literary trompe l'oeil: a book about friendship, writing and the boundary between reality and fantasy ... Dark, smart, strange, compelling' Harriet Lane, bestselling author of Her

Overwhelmed by the huge success of her latest novel, exhausted and suffering from a crippling inability to write, Delphine meets L.

L. embodies everything Delphine admires; sophisticated and unusually intuitive, she slowly but deliberately carves herself a niche in the writer's life. However, as she makes herself indispensable to Delphine, the intensity of this unexpected friendship manifests itself in increasingly sinister ways. And as their lives become further entwined, L. begins to threaten Delphine's identity and her safety.