Trying to get to the bottom of Billy's story, Strike and Robin Ellacott - once his assistant, now a partner in the agency - set off on a twisting trail that leads them through the backstreets of London, into a secretive inner sanctum within Parliament, and to a beautiful but sinister manor house deep in the countryside.
And during this labyrinthine investigation, Strike's own life is far from straightforward: his newfound fame as a private eye means he can no longer operate behind the scenes as he once did. Plus, his relationship with his former assistant is more fraught than it ever has been - Robin is now invaluable to Strike in the business, but their personal relationship is much, much more tricky than that
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