(NBC) — Tonight on “Dateline,” a bank executive is targeted by a crew of criminals who invade his home and take his mother hostage, ordering him to rob his own bank. Investigators think it looks like an inside job, but after a string of similar crimes, they learn the victims were picked by their social media posts.

Here is an excerpt from Dennis Murphy’s chilling report:

Investigators in another part of the country were about to uncover a whole series of similar crimes. Crimes that would span across two states, involving high-speed chases and even more victims.

Two months after the Connecticut home invasion, a guy named Mark Ziegler was on his way to work as the CEO of the Y-12 Federal Credit Union in a suburb of Knoxville. As he was pulling out of his garage, he noticed a garbage can was knocked over.

DAVID LEWIN: So, he puts his car in park, gets out of the car, goes to fix the garbage can. At which time, he is accosted by two masked men wearing dark clothing, ski masks, with guns drawn.

The assailants forced Ziegler back into his house. His wife and teenage son were inside. All three frightened family members were handcuffed and placed in the living room.

Mark Ziegler was then handed a three-page note. It contained chilling details on what was about to happen — Ziegler was going to rob his own credit union. If he failed, the consequences would be devastating.

DAVID LEWIN: For every minute that Mr. Ziegler was late, his wife was going to lose a finger. And when she ran out of fingers, their adult daughter, Britney — who lived in Texas at the time — they have people watching Britney in Texas.

DENNIS MURPHY: They had eyes on the daughter.

DAVID LEWIN: They had eyes on the daughter. And they were going to chop her up and mail her to the family if Mr. Ziegler failed to comply.

But what happened next took an even more bizarre turn.

Watch “Dateline” tonight on NBC4 at 9 p.m., right after an all-new “The Blacklist” for another “Crimetime Friday” you won’t want to miss.