In an abandoned mansion at the heart of Barcelona, a young man, David Martin, makes his living by writing sensationalist novels under a pseudonym. The survivor of a troubled childhood, he has taken refuge in the world of books and spends his nights spinning baroque tales about the city’s underworld. But perhaps his dark imaginings are not as strange as they seem, for in a locked room deep within the house lie photographs and letters hinting at the mysterious death of the previous owner. Like a slow poison, the history of the place seeps into his bones as he struggles with an impossible love. Close to despair, David receives a letter from a reclusive French editor, Andreas Corelli, who makes him the offer of a lifetime. He is to write a book unlike anything that has ever existed — a book with the power to change hearts and minds. In return, he will receive a fortune, and perhaps more. But as David begins the work, he realizes that there is a connection between his haunting book and the shadows that surround his home.