In the quiet of twilight, on an early autumn day, 26-year-old Elisa Vandersteel is killed while riding her bicycle along the Charles River. It appears she was struck by lightning - except the weather is perfectly clear with not a cloud in sight. Dr. Kay Scarpetta, the Cambridge Forensic Centre's director and chief, decides at the scene that this is no accidental Act of God. Her investigation becomes complicated when she begins receiving a flurry of bizarre poems from an anonymous cyberbully who calls himself Tailend Charlie.