Coraline: Neil Gaiman

When Coraline explores her new home, she steps through a door and into another house just like her own . . . except that it's different. It's a marvelous adventure until Coraline discovers that there's also another mother and another father in the house. They want Coraline to stay with them and be their little girl. They want to keep her forever!
Coraline must use all of her wits and every ounce of courage in order to save herself and return home.