Blood in the Water — David DeLee

What lies on the ocean floor? Buried Treasure. Deadly Secrets. A life's work. Sometimes even a dead body or two.
Benton Walsh and his wife Abby are on a mission. They've arrived on the Isle of Shoals along the New England seacoast for a very specific purpose. And they're being damn secretive about it.

Why? What are they up to? What does the eighteenth century pirate John Quelch and an old wives' tales of lost treasure have to do with it? And why would anyone want to kill them over it?