Blood in the Sand By Alex Sigmore

Sun, sand and champagne. It sounds like the perfect vacation, until the disappearances started. Local women are vanishing from the Caribbean island of St. Solomon and no one seems to know why. Even worse, the local authorities aren’t doing anything about it.

Determined not to let these disappearances get any worse, Special Agent Emily Slate goes undercover for the first time since her life was turned upside down, determined to find out who could be behind it all.

Except she’ll get more than she bargained for. The tropical island holds a deadly secret, one that may drag Emily under with no chance to come up for air.