IMPACT x Nightline: Season 4, Episode 13

4 - 13: Kill Code: Black Dahlia & Zodiac – Two Cases, One Killer?

The episode explores a controversial theory linking two of America's most famous unsolved crimes: the Black Dahlia murder and the Zodiac killings. An independent investigator follows a trail of cryptic messages, historical records, and forensic clues while asking whether both crimes could have been committed by the same killer.