at the time sidney moorer and tammy moorer owned a 2014 ford 150 truck. tigators discovered that apparent link between heather's disappearance and tammy and sidney moorer, they pay a visit to their house. >> originally, when the officer showed up at tammy and sidney moorer's house on december 20th of 2013, they noticed that there were cameras up outside the house. >> the goal after they saw that security system was to get a search warrant. >> however, once they went back, they found out that the surveillance system in there was a new system and that it had not recorded anything on december 18th of 2013. >> they had no idea what was on the new system, but they knew that they -- out of an abundance of caution, they needed to seize that system. >> investigators also scoured the moorers' black pickup truck looking for clues, and they made an important discovery. >> it was a brand-new f-150, fully loaded, had all the bells and whistles. in this truck was a gps navigation system. we learned that it was possible to disengage this system, and that's exactly what t