Walker and Munoz are back... and this time it’s personal.
When Maddie Walker’s friend, Samantha “Sam” Daniels, fails to show up for a final exam and a community service project, the teenager is convinced that something is seriously wrong, and takes it upon herself to look into it. She initially lies to her father and puts herself in a potentially dangerous situation. When all of her efforts fail to uncover Sam’s whereabouts, Maddie finally asks her father, retired FBI agent Craig Walker, to look into her friend’s disappearance. After venting his parental frustration over his daughter’s uncharacteristic behavior, Walker listens to Maddie’s concerns and eventually agrees to launch his own investigation – primarily to assuage his daughter’s worries.
It quickly becomes apparent as Walker investigates that Sam Daniels’ backstory is a complicated and troubling one. He shields his daughter as much as possible from this information and is almost ready to give up, when new evidence comes to light that suggests Sam is being held against her will.
Walker still has connections at the FBI, and he convinces his former commander to allow him to open an official investigation. Walker gets permission to partner with Detective Dave Munoz and another retired FBI agent Peter Stansky, and the three investigators find evidence that the disappearance of Sam Daniels is just the tip of the iceberg.