All-New The Prussian Blue Mystery Airs July 22 at 10 p.m./9 p.m. CT
When a San Diego woman arrives at an emergency room, she is near death. Her hair is falling out and her vital signs are fading, even though there are no signs of an infection or injury. Doctors, the FBI and local law enforcement are then called in to try to solve not only a medical mystery, but also a horrific crime. Natalie Morales reports.
VIDEO PREVIEW: https://nbcnews.to/2LYiUad
Dateline NBC is the longest-running series in NBC primetime history and is now in its 27th season. Anchored by Lester Holt and featuring correspondents Andrea Canning, Josh Mankiewicz, Keith Morrison and Dennis Murphy, Dateline is the #1 most-watched Friday newsmagazine for the last two straight seasons and reaches millions of people every week through its broadcast and social media platforms. This year, the series will be inducted into the Broadcasting & Cable Hall of Fame. David Corvo is the senior executive producer, and Liz Cole is the executive producer. Follow Dateline on Facebook, Instagram and Twitter.