In 2018, a spree killer shot and killed six people in Scottsdale and Phoenix, Arizona. The victims included a famous forensic psychiatrist, two paralegals, a counselor, and an elderly couple inside their home. Over 96 hours, the residents of Scottsdale were terrified that they would be next. It wasn’t until the police received a tip that turned their investigation upside. But even with a promising lead, detectives weren’t sure they had enough evidence to make an arrest.