In this dark thriller from bestselling authors Douglas Preston and Lincoln Child, Special Agent Pendergast stalks his wife's traitors from Scotland to New York City, where he discovers layers of deception and conspiracy that will shatter everything he believed to be true. Yesterday, Special Agent Pendergast still mourned the loss of his beloved wife, Helen, who died in a tragic accident in Africa twelve years ago. Today, he discovers she was murdered. Tomorrow, he will learn her most guarded secrets, leaving him to wonder: Who was the woman I married? Why was she murdered? And, above all ... Who murdered her? Revenge is not sweet: It is essential.