In a busy train station in Europe, a tourist finds a finger in a train station locker—and soon after, a matching body is discovered on the train. A new serial killer is at work, more cunning and diabolical than anyone can imagine—and FBI Special Agent is the only one who can stop him before he strikes again. FBI special agent Adele Sharp—a German-and-French raised American with triple citizenship—is made to criss-cross America and Europe to bring criminals to justice. But as more bodies begin to turn up, each missing a finger and abandoned on a train, Adele must race to uncover the meaning behind this twisted signature. Can she enter the killer’s mind in time to save the next victim? Or will this case take a darker turn than even Adele could imagine?