A body in a hospital isn't so unusual. Unless they've been murdered!1916, London: Keen to support the war effort, bookshop manager and sometime amateur sleuth Hannah Merrill has taken a volunteer role in the library of the nearby military hospital. But arriving at the hospital one cold winter's morning, she is horrified to find the body of a dead soldier in the library. What's more, a beautiful young nurse confides in Hannah that she thinks she's being followed, and then she abruptly disappears. Hannah can't shake the suspicion that the two cases are connected, but she can't solve the case alone. She'll once again need to call upon her delightful, demanding, only-occasionally devious aunt, Violet. The two women know they must find the missing nurse before it's too late. . . but they don't realise they're now both in the killer's sights.