. >> reporter: and we talked with tom fassbender, a lead investigator in this case, who has come under fire for this silent interrogation. you have stayed silent through the firestorm. why are you sitting here today? >> i finally realized that someone needed to speak out and tell the truth of what happened here. >> reporter: so, what did happen here? the story begins with the woman at the heart of this case, a 25-year-old photographer from wisconsin named teresa halbach. >> she just loved being behind the camera. >> kim peterson and teresa became friends in college. they both worked at the same studio in green bay and she said teresa had a special way with the subjects. >> she could make them smile. i think that's what she loved to do. >> reporter: the two stayed in touch after they launched their careers. but that would all change suddenly on october 31, 2005. kim caught a story on the local news. teresa was missing. >> investigators say the photographer was on assignment for auto trader magazine when she disappeared. >> i just kind of dropped knowing it was somebody i knew. >> report