Book excerpt: Sit, stay, die. Dogs aren't always man's best friend. When Amy sees a dog stranded on the side of the highway, she knows what she has to do. She tells her dad to stop the car. She can't understand why anyone would abandon a dog in such a way, tied up and blindfolded. Amy's parents say they'll only keep the dog until they can find it a permanent home. Amy's younger sister names the dog Rover.They take Rover into their house, their family. And once he's there . . . he doesn't want to leave.Amy loves dogs. But she starts to worry when strange things start happening in the house.Objects move. Lights go off. Accidents happen.Soon man's best friend has turned into Amy's worst nightmare.The problem isn't Rover's bark or his bite - it's even creepier than that. This dog's purpose is evil . . . and if's waiting to be unleashed.