The book is about a reality TV producer, Laurie, whose husband was murdered in front of their toddler son. The murderer was never caught so they are under perpetual fear. The book is also about the Laurie's new show which is to be about unsolved murders. The pilot for this show is about a rich woman being murdered at a graduation party. Literally everyone hated this woman, but the mystery is in who killed her and also who killed Laurie's husband and where that person might be.
I would still suggest reading it if you are a die hard Mary Higgins Clark fan, but it is definitely not her best work.