Agatha Christie publishes Postern of Fate

Now in their seventies, Tommy and Tuppence move to a quiet English village, looking forward to a peaceful retirement.

But, as they soon discover, their rambling old house holds secrets. Who is Mary Jordan? And why has someone left a code message in an old book about her 'unnatural' death? Once more, ingenuity and insight are called for as they are drawn into old mysteries and new dangers.