Peter Crag and John McCleary, both former Philly Homicide cops, operate a small and not very successful private detective agency in Philadelphia. John McCleary is found dead under a boat in Harrah’s Marina Casino harbor in Atlantic City, an apparent accidental drowning. A chance encounter leads Crag to believe his partner had been murdered, why and by whom unknown. Crag is driven by that most primal of urges, the honor-bound duty of a cop to avenge his friend and partner. Unraveling the mystery leads Crag to the grimy streets of Philly strip clubs, a gentleman’s suddenly sinister country estate in the beautiful rolling hills of Bucks County, the glitz of Atlantic City casinos, the seemingly senseless murder of his long time woman, a car containing a young couple and a million dollars at the bottom of a quarry, a former minor league baseball player in a bullet riddled wetsuit, and a bizarre marriage between a man he thought he knew and a beautiful woman in a freezer.
This is a run down of the plot. What happens if he doesn't solve the case? Why should we care? I love a good detective yarn as my library thing list shows, but you've got to give me some specifics to entice me to read the book, and care about the characters.
Your hook is probably that he's not a good detective but if he doesn't solve this one he'll be the next one in the freezer kind of thing. You'll want to twist that around and make it your own cause it's a bit long in the tooth as hooks go, but you get the idea.