Not a Word by Lynwood Barclay

When Reece stops by his parent’s home for a visit, he finds his parents dead from an apparent murder-suicide. As the police begin their investigation, he gets a call from his mother. So who’s the dead woman with his father. Over the next couple of days, he frantically searched for the truth, learning that his parents were not the people he thought they were.

With all the twists and turns that you expect from this master of the thriller genre, you won’t be disappointed.