still in the embryonic stages, leaving a real mystery in the tiny oklahoma town who killed mary morgan hewitt in the wake of mary's death, her grief stricken grandfather, david morgan, became a citizen investigator. he was thorough and strong and determined to find out what happened to my mom. >> so determined. he retired early from halliburton. he went back to college and received his criminal justice degree. >> as he researched mary's murder, he wrote down his questions and suspicions like who had a key? kyra shared his notes for the first time with true crime news that he mentions that he's not sure that my mom drove her car because there was ruts in the driveway and her car wasn't parked in the ruts. >> he just said, you know, mary is a creature of habit. she always parks the same way. >> other clues david morgan noticed the outside light was off. it was always on. if she was home, if she let someone in, she trusted them. and the 38 was still in the case at the time. kyra, who was just a young girl, had no idea what her grandfather was consumed with. >> we pretty much were told to forget