José Díaz-Balart

Sana got worried.

I mean, you were exchanging information 24 hours before, and she never mentioned that.

Sana called Ana's estranged husband, David.

He said he was at home in Florida and had not heard from her.

Then she called Elisa, who told her she had received the same strange text from Ana, but in Spanish.

Elisa learned that Ana failed to show up for a train trip she had planned with another close friend, so the friend reported her missing.

That's when panic set in.

Firefighters went to Ana's apartment to conduct a welfare check.

Spanish police followed.

They found no forced entry, no signs of violence, and no Ana.

Sana couldn't wait any longer.

She jumped on a plane bound for Madrid, hoping she and Elisa could find Ana.

And they wouldn't have to do it alone.

Alex Montilla, then an agent with the FBI, took on the case after Ana's family notified the bureau that she was missing.

What did your gut tell you?

Agent Montilla would eventually fly to Madrid herself to investigate.

And that, that is her apartment?

And this is where the investigation begins?

What all three women discovered would become the focus of an international manhunt.

Less than one week after her best friend Ana disappeared, Sana Ramo flew to Madrid, determined to find out what happened to her.