The Broberg family live a peaceful existence until B., a charismatic new neighbour, takes a shine to them ... and disappears one day with their eldest child, Jan.

With the help of FBI agent Pete Welsh, Bob and Mary Ann Broberg do everything possible to find their missing daughter. Meanwhile, in Mexico, Jan is brainwashed and given a secret mission.

Flashbacks reveal the way B. became so intertwined with the Broberg family and uncover the mystery surrounding Bob and B.'s chilly relationship.

With Jan finally home, the Brobergs try and fail to resume normal life, but they are each living a secret nightmare. Bob is blackmailed, Mary Ann is seduced, and Jan prays for guidance from people she believes are watching her every move.

Mary Ann sets a boundary with B., but too late. Distracted by their disintegrating marriage, Bob and Mary Ann see Jan slip through their fingers once again as she leaves for Wyoming with B.

While spending her 14th birthday with B., Jan struggles with her mission and adopts a more grown-up persona. Bob and Mary Ann come together to bring Jan home from Wyoming, and just when it seems they've succeeded, she disappears again.

For the second time, Jan is a missing person, as B. gives her a false identity and enrols her in a boarding school in California. Agent Pete Welsh, ignoring warnings to stay away from the case, uncovers a shocking betrayal.

Pressure mounts to find Jan: the Brobergs are at the end of their rope and take matters into their own hands. But the authorities finally locate B., arresting him and bringing Jan home. To the Brobergs' dismay, however, she is still brainwashed.

Disaster looms as Jan's 16th birthday is on the horizon. Her failing the mission would mean her failing everyone she loves... or would it? She considers an unthinkable choice as she finally grapples with the lies B. has told her.