. >> the jail yard but he was named robert mullins, a petty crook who seemed strangely interested in to you about the case? >> all the time. >> but then it seemed everything in this part of south carolina wanted to know more about this case and it's two beloved victims. it took three years but in 2008, the state was ready to try rick gagnon for the murders of charlie and diane parker. the camera was rolling as prosecutor humphreys began the case. >> this establishes the motive for richard gagnon to in the lives of these two people. >> as humphreys recalls, the case against rick was always motivation strong, evidence week, not more than a drop of charlie parker's blood on a shoe when it came down to it. even so, humphreys told the court he got the footprint of the murder scene. >> he had a story for it, didn't he? >> yeah, he did. it didn't hold water but he had a story about it. >> charlie recited his version of how he had gone into the parker house to get a set of car keys sometime after the crime scene techs had finished up. >> he looked to his right, which was a window leading into