>> what we hoped to find out was did he purchase gas or an accelerant there that could be used to start the fire? >> unfortunately, there were no video surveillance cameras at that gas station. investigators discovered that wallace did have a connection to mississippi. >> wallace had some connection to mississippi in that he had some relatives that were there. >> while investigators searched for wallace, they also had to search for forensic evidence, and they weren't having much luck inside olamide's apartment. >> it's a common misconception that there are hundreds of fingerprints left at every crime scene. and a lot of times, you may only find one, or you may find none. >> since the crime was committed at night, investigators assumed the killer would have turned off the lights after cleaning up the blood, but there were no visible bloodstains on the light switch by the door. >> that whole area was actually brought into the laboratory. they cut out the wall and took the light switch and brought in all of that to us. >> analysts viewed the switch plate with oblique or angled