“It was an extraordinary sensation to hear those voices speaking out across the years, sometimes so choked with emotion as they described losing hold of parents or children in the cold water,” says Preston. The relic so intrigued Preston, a noted historian and author of The Boxer Rebellion, that she would devote three years to investigating the incident and conduct dozens of interviews, trying to better understand “how a ship carrying civilian men, women and children could have been sunk without warning.” She tracked down passengers’ families, pored over military documents in England, Germany and the United States, plunged into the files of the ocean liner’s company, Cunard, and listened to interviews with survivors and witnesses recorded decades ago by the Canadian Broadcasting Corporation. Diana Preston traces her investigation of the sinking of the Lusitania, the British passenger liner torpedoed in May of 1915 by a German submarine off the coast of Ireland, to the day in 1998 that she came across the ship’s “giant bronze propeller, stark as a dinosaur bone, sitting on the quayside in Liverpool’s docks.”