DNA unravels murders of Erin Gilmour, Susan Tice on ‘Dateline’

(NBC News) — On Friday’s new two-hour “Dateline,” Josh Mankiewicz reports on the four-decade-long murder investigation in Toronto that was finally cracked thanks to old-fashioned detective work combined with breakthroughs in genetic genealogy.

Here is a preview of Mankiewicz’s report:

It doesn’t matter where you live, evil can come through any door. On one awful night, it found its way here.

ANDREW: There was blood everywhere.

Twenty-two-year-old Erin Gilmour had been found dead in her apartment.

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KRISTIN: I still have dreams of wishing I could have been there to have helped.

And Erin’s killer remained elusive.

ANDREW: He was a ghost.

Whoever it was had vanished like a breath on a freezing night. The case had gone cold. It stayed that way for years. That’s when something happened thousands of miles away.

SEAN: It was like a lightning bolt.

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A decades-long investigation would lead to the middle of nowhere. To a father, friend, solid citizen.

RANDY: So, you’re telling me the truth, right? And his tears were coming down his face.

To see what breakthroughs led big city detectives to a tiny remote town to find the killer, watch “Dateline: Evil Walked Through the Door,” Friday at 9 p.m. on NBC4.

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