Mr. Mercedes by Stephen King
A living cliché of a retired ex-cop spends his days watching television and staring into the barrel of his service revolver. Then a snotty psychopath terrorist style killer decides to antagonize him and give him a reason to live. The old cop finds loves, does some detecting, and eventually uncovers the killer’s evil plot to… Well, you’ll have to read on to find out more, won’t you?
Pretty forgettable, this one.