calling her a psycho whore. >> she could've said, oh i'm so sorry this girl is missing and i hope you find her. and left it alone. but no, she goes on the attack. >> tammy was the one with the motive. she is the hunter. >> and it was a hunt. the prosecution said, the investigator told the jury he'd use cellphones added to track the moorer movement. in the days before the disappearance, they showed up near heather's workplace. some of the bars she liked, even her home. the prosecution suggested the couple was stalking her. then, in the early hours of december 18th 2013, with heather's roommate out of town, the prosecution said that the couple struck. it began here, the prosecution showed the jury surveillance video of sydney walking into a walmart and purchasing a pregnancy test for heather. >> as soon as they leave for walmart, they go and call her. why? because the test is for her. >> the prosecution's theory was that sydney had called heather