tirelessly to free them from prison, we pose the questions everyone has been asking to two men who helped put avery and dassey behind bars. >> why would steven avery do this? >> great question. >> we speak with former prosecutor can kratz who's written a book which reveals his provocative theory. that steven avery made himself a murderer. >> stephen avery started planning this event the very first day he went to prison. >> and we talk with tom fassbender a lead investigator in the case who is come under fire for this controversial interrogation. >> you've stayed silent for this firestorm. why are you sitting here today? >> realized that someone needed to speak out, to bring forward the truth of what happened. >> so, what did happen here? our story begins with a woman at the heart of this case, a 25-year-old photographer from wisconsin named teresa halbach.