Breathless by Dean Koontz

Breathless: A Novel of Suspense - Grady Adams and his dog Merlin encounter two animals like no other.  At the local veterinarian office of Dr. Camillia Rivers, several dogs rescued from an illegal puppy mill, suddenly Camillia Rivers become happy and content.  Henry Rouvroy traveled across the country to take over the life of his twin brother.  In Las Vegas, Dr. Lamar Woosley, a specialist in chaos theory performs several acts of kindness that seem coincidental.  Along the coastal highway, panhandler Tom Bigger sees something so unusual he stops drinking and heads to his childhood home.  In suburban Seattle, Liddon Wallace hires Rudy Neems to kill his wife. THEN, the government gets involved and everyone's life is turned upside down.