Sex, Lies & Diamonds — Kris Calvert

After eighteen months in the Mediterranean, newlyweds Polly and Leo Xanthus can barely keep their hands to themselves. The Greek isles have warmed their skin and hearts, but each longs for a life where they never have to hide from the mafia that forced them into seclusion.
The Marcello crime family is on the brink of going under. With their revenue streams drying up and the feds ever-present on their tail, aging crime boss Alfonso Balivino looks to steal a diamond owned by his one-time boss, Kostas Xanthus to fund the family.
Now, Polly and Leo will be forced to leave their unknown location and find their way home to New Orleans before the Marcello family murders again, forcing them and the ring on Polly's hand out of hiding.
But the diamond is more than a stone. It's a puzzle. A password to something monumental. And when Polly and Leo discover it's the key to riches far greater than anyone could imagine, the race is on -- not only to stay alive but to stop a heroin empire.