Will o' Wisp

London, the closing decades of the nineteenth century. Hanna inherits two keys from her grandfather's collection of objects. Testing them, she finds that one opens the door to the basement, and the other unlocks a small box she has not noticed before. Inside is a doll. Something about the doll, and the two keys, and why her grandfather had them, draws Hanna into a mystery that begins in the basement and does not end there.