(NBC News) – Tonight on “Dateline,” when soldier Vanessa Guillen vanishes from Fort Hood, her family does everything they can to bring attention to her disappearance.

As weeks go by without any sign of Vanessa, revelations about her case inspire a movement.

Here’s a preview of Andrea Canning’s report:

Voice #1: I couldn’t believe this was happening to me. It was the scariest part in my life because I was alone.

So many were quiet. For so long.

Voice #2: I was harassed, sexually assaulted, raped, and physically threatened.

Voice #3: This man that I trusted… I felt violated, I felt stupid.

But now? Now they want to be heard.

Voice #4: The men who sexually assaulted me are still serving in uniform today.

Voice #5: There is no excuse for harassment. It has to stop.

All these voices inspired by one that suddenly, last April, went silent.

Tonight, “Dateline” questions Secretary of the Army Ryan McCarthy about the investigation and allegations of sexual assault in the military.

Watch “Dateline” tonight on NBC4 at 10 p.m.

About “Dateline”

“Dateline NBC” is the longest-running series in NBC primetime history and is in its 30th 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.

This past season, Dateline debuted two new podcasts, “Mommy Doomsday” and “Killer Role,” hosted by correspondent Keith Morrison.

In February, NBC also greenlit a straight-to-series inspired by the story featured in the Dateline podcast series, “The Thing About Pam.” Two-time Oscar-winning actress Renee Zellweger will star and executive produce the series, in collaboration with Blumhouse Television, NBC News Studios and Zellweger’s Big Picture Co.