On May 5, 2016, Filmmaker John MacGibbon receives a call from Quincy College's Plymouth Campus informing him that his mother-in- law, Vibeke Rasmussen, has not shown up for work. Alarmed, John contacts local authorities, and the couple drives from their home in Cambridge, Massachusetts to Rasmussen’s apartment an hour away. When they arrive, police refuse to give them any information about what they've found. The couple leaves not knowing what to think-- one officer suggests Rasmussen may have committed suicide. Hours later police call to share an unimaginable truth-- seventy-six-year- old Rasmussen has been stabbed more than 35 times in the face, neck, hands and shoulders while in bed in her Plymouth apartment. It was a murder so gruesome in its brutality that a forensic expert said the evidence showed the killer continued to stab Rasmussen even after she was dead. “She’s not moving and he’s not stopping.” Police immediately talk with everyone in the apartment complex and only one person is missing; Rasmussen’s new neighbor across the hall, 24-year-old Tyler Hagmaier. A picture of Tyler begins to emerge - a privileged young man with a repressed, tragic, and violent past. Police begin the search for Hagmaier, and MacGibbon begins his own investigation into what drove this man to viciously attack and kill his wife's innocent mother.