When Nathan Isaacs walks suddenly back into Jaci Williams's life, she wonders if she ever knew her ex at all. Because it turns out he was a government-trained killer…and the only thing standing between her and death. Nathan gave everything to his country—his life, his family, even the one chance he had for happiness with the woman he loved. Then the agency he worked for betrays him, and they're targeting Jaci, too. Now their only chance of survival lies in finding out why someone wants them dead.