Paradise Cove / Davin Goodwin.

Enhanced descriptions from Syndetics:

Every day is paradise on Bonaire--until something unexpected washes ashore

On the laid-back island of Bonaire, every day is paradise until a seaweed-entangled human leg washes ashore. Combing the beach, retired cop Roscoe Conklin examines the scene and quickly determines that the leg belongs to the nephew of a close friend.

The island police launch an investigation, but with little evidence and no suspects, their progress comes to a frustrating halt. Then, thanks to a unique barter with the lead detective, Conklin finds himself in possession of the case file. He can now aggressively probe for his own answers.

Sifting through the scant clues, eager to bring the killer to justice, Conklin struggles to maintain forward momentum. He has all the pieces. He can feel it. But he'd better get them snapped together soon.

Otherwise, the body count will continue to rise.

For fans of John Sandford's Lucas Davenport and Virgil Flowers--Only substitute sun and sand for snow and ice

While the novels in the Roscoe Conklin Mystery Series stand on their own and can be read in any order, the publication sequence is:

Diver's Paradise
Paradise Cove