Fourteen years ago, investigators ruled Philadelphia teacher Ellen Greenberg's death a suicide — despite the 20 stab wounds covering her body, including 10 on the back of her neck. "Death in Apartment 603: What Happened to Ellen Greenberg?" The Greenberg family never believed this finding. Nancy Schwartzman, the director and showrunner of "Death in Apartment 603," said she also struggled to accept the investigators' conclusions when she learned of the Greenberg case. "Death in Apartment 603" arrives as the Greenberg family awaits its next court hearing.