The U.S. government has sanctioned two top-secret scientific experiments, both morally questionable and potentially devastating. The brainchild of a noted pop-psychologist - overseen by a shadowy figure known for his brutal efficiency and cold disregard for human life - these twin covert operations are each part of a dark and sinister agenda: an attempt to use Multiple Personality Disorder to create the perfect assassin.Major Roger Grayson's uncanny ability to adapt to any undercover situation by becoming seemingly different people makes him the ideal person to evaluate both these projects.
Adam Whistler has spent his entire life within the shadowy region populated by government operatives and contract killers - first those employed by his father, and then in the service of his own country under the sinister Felix Aubrey. At the age of 34, he has put that life behind him and to ensure he will walk away unharmed, he has taken as security Aubrey's ledger containing a list of prominent people who received money from illegal search-and-seizures.
Elizabeth Stride has settled on South Carolina's Hilton Head Island to escape her past. Most of all, she wants to leave behind Martin Kessler - a man who will always own a piece of her soul. But his love is a continuing reminder of what she once was: "The Black Angel", a ruthless and efficient assassin.