The old mansion stood silently at the edge of town, its windows dark and empty like the eyes of a skull. Detective Sarah Morgan stepped out of her car and pulled her coat tighter against the bitter cold of the December night. She had received the call exactly one hour ago, and the dispatcher's trembling voice still echoed somewhere deep inside her head. A body had been found in the library, sprawled across an antique desk that was now stained dark red with blood. The victim was a wealthy man named Charles Pemberton, who had invited twelve guests to his home for a holiday dinner party. No one had heard a scream or any struggle, and every single guest claimed to have been elsewhere when the murder occurred. Officer Jenkins met her at the front door and handed her a pair of latex gloves without saying a single unnecessary word. The chandelier in the foyer cast long and twisted shadows across the marble floor as Sarah walked steadily toward the crime scene. She knelt beside the body and noticed a small piece of torn paper clutched tightly in the dead man's pale right hand. Someone in this house was a killer, and Sarah knew that before the night ended she would find out exactly who.