(NBC News) — On Friday’s all-new two-hour “Dateline,” a chilling mystery unfolds when a terrified teen calls 911 reporting the screams of her mother, Mary Ann Murphy.

A seasoned detective is convinced the key to unravel Murphy’s brutal murder lies within her house. “Dateline” correspondent Keith Morrison shows how investigators solved the brutal killing and uncovered a dangerous romance.

Here is a preview of Morrison’s report:

It was the middle of the night just outside of Houston. Keri Murphy, a tearful 16-year-old girl, pleaded with 911 to send help.

JUAN VIRAMONTES:  She heard a male’s voice telling her mother to shut up. And then she ran out of the house.

The veteran detective just knew — the house was telling him something.

SCOTT MURPHY: They fingerprinted me. They fingerprinted my dad.

HEATHER TUCKER: She told me that she felt as if the police were trying to make it seem like she did it.

What happened on that dark summer night? It wasn’t long before investigators found themselves heading down a rabbit hole.

SCOTT MURPHY: The bunny phone.

KEITH MORRISON: The bunny phone.

Watch “Dateline: Down the Rabbit Hole,” Friday on NBC4 at 9 p.m. on NBC4.