(NBC NEWS) – Tonight on “Dateline,” following a night at her friend’s bachelorette party, 23-year-old Kaylee Sawyer disappears. Soon after, an intense multi-state manhunt leads investigators to the killer.

This episode features new interviews with Kaylee’s mom and the family’s lawyer after they reached a settlement with the killer’s employer, as well as never-before-released deposition tapes with the killer’s co-workers.

Here’s a preview of Keith Morrison’s report:

July 23, 2016. Lisa was celebrating her upcoming wedding. The bachelorette party was for her. Kaylee had already told Lisa and her sister Jana that she couldn’t go; she’d be out of town. But, last minute…

LISA CASTRO: I got a text from her saying, “Guess what? I’m gonna show up to your party to help celebrate you. But I’m gonna show up a little late. But I’ll be there!”

KEITH: That’s a great thing, when women get together for a bachelorette party. Katie, bar the door.

LISA CASTRO: Especially at our age.

KEITH: She was kicking up her heels a little bit, right? Am I correct?

LISA CASTRO: Yes she was having fun.

But, when the bachelorette and her party began to run out of steam, Kaylee and a friend left to keep things going at another bar downtown.

JANA: You know I checked ’em out and said, “You know, you girls be safe. You’re OK, right?” And they said, “Yeah, we’re OK. We’ll be good.”

And a little before 10:30 p.m., she walked out into the night – happy – a little tipsy. Altogether unaware of what was waiting on the other side of midnight.

Watch “Dateline” tonight at 9 p.m. on NBC4.

About ‘Dateline’

“Dateline NBC” is the longest-running series in NBC primetime history and is in its 31st season. Dateline is anchored by Lester Holt and features correspondents Andrea Canning, Josh Mankiewicz, Natalie Morales, Keith Morrison and Dennis Murphy.

Dateline is the #1 Friday newsmagazine and reaches more than 17 million people every week through its broadcast, and millions more through its social media platforms and podcasts.

The stories range from compelling mysteries to powerful documentaries and in-depth investigations. When major news breaks, they go to the scene, putting the pieces together to bring the viewer the full picture. And in every story they tell, they help the real people who lived the events share their journeys with the viewer.