Lilian Delaney, apprentice to a master bookbinder in Oxford in 1901, chafes at the confines of her life, caught between the oppressive walls of her father’s bookshop and the limitations of being a woman in a man’s profession. But when a burned book comes into her possession, she finds hidden beneath the binding a fifty-year-old letter speaking of love, fortune and murder.

Lily is drawn into the mystery, which hints at a forbidden romance between young lovers, and learns there are other books which conceal more of the story. Lily becomes obsessed with finding them, but she is not the only one looking, and what began as a simple intrigue quickly turns dangerous.

Her journey takes her across the country, to the eccentric booksellers of London, private libraries of unscrupulous collectors and the dusty archives of society papers, as she delves further into the heart of the secret. But with sinister forces closing in, willing to do anything to obtain the books, Lily’s world begins to fall apart, and she must decide if uncovering the truth is worth losing everything.