The No.1 bestselling classic from Dean Koontz, the master of chilling suspense, that will thrill fans of Stephen King and the Odd Thomas series.
 
They escape from a secret government project: two mutant creatures, both changed utterly from the animals they once were. And no one who encounters them will ever be the same again.
 
A lonely widower, a ruthless assassin, a beautiful woman, a government agent.
 
Drawn together in a deadly hunt, all four are inexorably propelled towards a confrontation with an evil beyond human imagining.