On the bleak island of Ray, off the Essex coast, an idealistic young doctor, Simeon Lee, is called from London to treat his cousin, Parson Oliver Hawes, who is dying.

Parson Hawes, who lives in the only house on the island – Turnglass House – believes he is being poisoned. And he points the finger at his sister-in-law, Florence. Florence was declared insane after killing Oliver’s brother in a jealous rage and is now kept in a glass-walled apartment in Oliver’s library.

And the secret to how she came to be there is found in Oliver’s tete-beche journal, where one side tells a very different story from the other. 1930s California. Celebrated author Oliver Tooke, the son of the state governor, is found dead in his writing hut off the coast of the family residence, Turnglass House.

His friend Ken Kourian doesn’t believe that Oliver would take his own life. His investigations lead him to the mysterious kidnapping of Oliver’s brother when they were children, and the subsequent secret incarceration of his mother, Florence, in an asylum. But to discover the truth, Ken must decipher clues hidden in Oliver’s final book, a tete-beche novel – which is about a young doctor called Simeon Lee .