Beatrice Wren is mad.

Or so her neighbours believe. An unmarried woman, living alone in Victorian London, and whispering to old trinkets she finds at the shore of the Thames.

When a box of porcelain figurines reveals evidence of a brutal murder, her carefully maintained isolation begins to crumble. Each new clue threatens both her sanctuary and her tenuous grip on reality.

Her investigation leads to Grim, locksmith by day, criminal by night, with a talent for breaking more than just locks. He offers help while hiding his true motives that are as dark as the vengeance he seeks. Together, they hunt a killer who might exist only in Beatrice's fractured mind.

As the evidence mounts, so too do the signs of Beatrice's madness. But if she is truly insane, why does the trail to the murderer point to an even darker truth about her past?