A missing mummy. A drug cartel. An ex-US Army Ranger. And a woman at odds with the world. It's Relentless...

There's no hiding the fact that Julia Collins has issues.She's shy to the point of trying to become invisible. She has OCD tendencies—breaking out in hives if she loses control of her environment. She finds it hard to talk to intimidating men, or more accurately, to any men. A fact that makes working as the office manager for Benson Security particularly difficult—the company is made up almost entirely of huge, intimidating,ex-military men. But none of the men affect her the way Joe Barone does. The ex-marine is charming, confident, heroic and so sexy it hurts to look at him. Everything about Joe intimidates Julia. And that's why, when he declares his interest in her,she does the only sensible thing—she hides.
There's a limit to how long Joe Barone is going to tolerate Julia hiding. So what if she has a few issues? They don't detract from her many attributes. She's gorgeous, smart, generous and kind. Which guy wouldn't want a woman like that by his side? So when her grandmother gets arrested in South America, Joe sees a perfect opportunity to show Julia how good they'd be together. Julia needs someone to accompany her to Peru, someone who speaks Spanish and who doesn't crumble in the face of authority. Julia needs Joe.

But when they get to Lima, they discover things are much worse than they were led to believe. With danger at every turn and lives on the line, Julia is forced to get past her issues and trust in Joe—her life depends on it.