The Hidden — Bill Pronzini

A series of seemingly random murders along a fifty-mile stretch of the rugged northern California coast, committed by an unknown dubbed by the media the Coastline Killer. A young couple with marital problems, Shelby and Jay Macklin, who decide to spend the week between Christmas and New Year's at a friend's remote coastal cottage. Two couples in a neighboring home whose relationships are thick with festering menace. A fierce winter storm that leads to a night of unrelenting terror. These are the main ingredients in Bill Pronzini's chilling and twist-filled tale about the hidden nature of crime and its motives.