Gone Before Goodbye by Harlan Coben and Reese Witherspoon

 I found the beginning of this story a tad confusing and the rest of it kind of dark. Maggie is a skilled surgeon and combat veteran whose life is falling apart. She has lost her medical license and is floundering. It takes quite a while to figure out exactly what happened to Maggie that led to this downward spiral. 

The story starts with a chaotic scene in a battle zone. Marc, Maggie's husband and a fellow surgeon, is doing emergency surgery when the camp where he's operating comes under attack. He alone stays to finish the surgery and is soon discovered by rebels with bad intentions. But we don't find out how that ended till much later in the book.

Back in the present, Maggie crosses paths with her old mentor, who says he has a job opportunity for her but can't give her details. She really needs the money they're offering, so reluctantly takes a chance--and lands in a nightmare with Russian oligarchs, stolen organs, and a mysterious woman named Nadia.

I kept reading till the end but found the story kind of disturbing.