Under the Surface (Harlequin Blaze Series #836)

Lusting after the enemy 

Former SEAL Jackson Duchane has spent almost a decade hunting down the wreck of the Chimera, a Civil War–era ship rumored to be filled with gold. Now he's agonizingly close to the biggest discovery of his life. With a rival diving team hot on his tail, Jackson is determined to get there first, but he didn't bargain on a sexy distraction… 

Heading up a diving team is Loralei Lancaster's nautical nightmare. Fortunately, nothing distracts a girl from her water phobia like a gloriously ripped surf god. And Jackson is hot enough to make Loralei forget everything—including the fact that he's an arrogant jerk! And when heated words lead to steamy nights, Loralei finds herself caught between the devil and the deep blue sea!