The FBI's special-crimes unit has been tracking an elusive criminal network for years without a breakthrough. Until now. Agents Brumfield and Lang must capitalize on a new intelligence in order to uncover and eliminate a major threat before the criminals disappear. But a troubling new question begins to emerge: What is Highway X? Caleb and Maggie Schultz are adjusting to their new reality now that their dad has been captured by the feds and locked away behind bars. Now Caleb is faced with an impossible choice: step into the criminal underworld to save his sister, or risk losing her forever...