The watchmen
(Book)

An Al Qaeda prisoner named Ali Zattout is moved from Pakistan to a CIA safe house for observation and interrogation. He is smart, cooperative, and thoroughly Westernized -but is he too good to be true? The man who must question him, Dr. Louis Finney, regrets his days spent working for the U.S. Government. Years have passed since he and his mentor performed experiments designed to develop multiple personalities in unsuspecting patients, but only recently have his guilty nightmares begun to subside. Now his mentor appears on Finney's doorstep, terminally ill, asking him to consult for a critically important CIA case. But the CIA isn't the only group interested in Zattout's information. His capture has aroused concerns at the highest ranks of Al Qaeda. An assassin schooled in ancient arts of meditation and murder is sent to eliminate Zattout before he discloses their secrets. The CIA safe house is as heavily guarded as the secret of its location, but Zattout is not the only traitor within its walls.