'NBC Dateline' takes a terrifying turn in all-new episode

"Dateline" is all-new Friday with a case that begins with a phone call.

Gelareh Bagherzadeh had left her boyfriend for the evening, promising to call upon her return, but it is a conversation with a friend that kicks the story off.

Bagherzadeh is found murdered after her close friend hears her screaming on the phone.

The craziest part? This case remained unsolved until the mysterious death of her boyfriend's brother. Now that case is personal.

Who wanted to kill these people and what connection does the killer have to the boyfriend?

Find out tonight as Josh Mankiewicz reports on the family feud that ended in these two murders.

Cox Media Group