1880s England

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. Secrets are uncovered in Oliver’s tête-bêche journal, where one side tells a very different story from the other.

1930s California

Celebrated author Oliver Tooke 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. To discover the truth, Ken must decipher clues hidden in Oliver’s final book, a tête-bêche novel – which is about a young doctor called Simeon Lee.