Overview: Reporter Caryn Lieberman reveals how Larry Arnold's murder investigation is linked to the 1997 killing of a 20-year-old woman hundreds of kilometers away in North Bay, Ontario. Sarah Whitehead was sexually assaulted and murdered as she left a mall. Both murders were mysteries that almost went unsolved, two seemingly unrelated cases, until DNA from a cigarette butt led police to the killer. A serial rapist and murderer whose crimes crossed provincial borders and some of which likely remain unsolved to this day.