Pilgrim is the codename for a man who doesn't exist. The adopted son of a wealthy American family, he once headed up a secret espionage unit for US intelligence. Before he disappeared into anonymous retirement, he wrote the definitive book on forensic criminal investigation. But that book will come back to haunt him. It will help NYPD detective Ben Bradley track him down. And it will take him to a rundown New York hotel room where the body of a woman is found facedown in a bath of acid, her features erased, her teeth missing, her fingerprints gone. It is a textbook murder - and Pilgrim wrote the book. Click here to read more.