Hearts in Vegas (Harlequin Super Romance Series #1934)

"You're not going into this alone." 

P.I. Frances Jefferies is the perfect person to slip into Las Vegas's underworld to recover a priceless necklace. With her elite investigative skills, not to mention her jewel-thief past, she knows she can get the job done. That is, until a sexy stranger gets in her way. 

Braxton Morgan's past is as secretive as her own. There's so much about this man she wants to discover—but not at the cost of her case. For that, she must stay focused. Then Braxton suggests adding his security expertise to catch the criminal. And suddenly they're mixing smarts with danger and a whole lot of passion!