Mr. Murder

Because he has a happy marriage, two adorable small daughters, and a successful career, mystery writer Marty Stillwater counts himself a lucky man. But all this is shattered when a stranger breaks into his house one rainy afternoon to announce: "You stole my wife, my life, and my children. I want them back." Claiming to be the real Martin Stillwater, the madman wages a relentless and terrifying campaign to eliminate Marty and recapture the family and life he believes to be his.
When even bullets fail to stop this savage intruder, the police are hard-pressed to believe the Stillwaters' harrowing account. Unable to rely on the protection of the authorities, the family goes on the run. But no matter where they hide, their enemy finds them.
In Mr. Murder, Dean Koontz creates the most endearing family to appear in a novel in a long time, makes us love themand makes us tear for them as they cross the path of a psychotic killer unlike any who has previously haunted the pages of fiction. Exploring contemporary society's tendency to draw an ever-thinner line between fiction and reality, Mr. Murder is blisteringly paced, terrifying, thought-provoking, and utterly fresh.