A pair of detectives investigate stalkers in Los Angeles. Strong and focused, Lt. Beth Davis is an expert in the field of repeated harassment, driven by personal experience of being a victim. She heads the LAPD's Threat Assessment Unit, which investigates cases of stalking -- including voyeurism, cyberharassment and romantic fixation. The history of recent transfer Jack Larsen -- whose personality and questionable behavior have been an issue in the past -- may help him in his assignment to her team. Her other detectives are young but eager Ben Caldwell and deceptively intelligent Janice Lawrence. Together they try to stop situations from spinning out of control -- and to keep their personal obsessions at bay.