Soundproof by Jo Chambliss

Missions sometimes go wrong. Sometimes, when you’re sent to rescue five missing American women, the camp where they’re being held gets bombed before you even arrive.
When you’ve grown up the way Tyler “Hawk” Morgan did, going back home with two body bags and no survivors doesn’t sit right. Not when the other three women are still out there suffering unimaginable horrors.
Cailyn, a caring, bubbly nurse, puts her life on hold to accompany her two favorite patients on a bucket list trip of a lifetime to Europe. The trip is a dream come true until suddenly coming to a nightmare end in Spain.
Captured and trafficked out of the country, Cailyn is sure of what her fate will be until her two brave friends pull off a miracle and convincingly disguise Cailyn as a young boy. Living out her time as a house servant to the terrorist cell, she hears and understands their plans thanks to growing up with an Arabic friend.
Hawk can’t sleep. Plagued by the nightmares of his past and what the missing women are being subjected to, Hawk skirts Navy chain of command, risking his career to find what military intelligence missed. He’s determined to bring the women home. That’s when the real fight to save Cailyn begins.