Back in 2016, a few weeks after the presidential election, something very strange started

happening in Cuba.

A CIA officer got sick after hearing this weird, high-pitched noise in his home.

A few more undercover agents started reporting the same thing.

What felt like a beam of sound aimed directly at them.

A pressure that wouldn't go away until someone opened a door.

The United States started investigating.

So did Cuba.

But no one could figure out what was going on.

It was a complete and utter mystery.

A good reporter like a good detective is always challenged by a mystery.

Sebastian Rhotela is a good reporter at ProPublica.

And in this world of intelligence and national security, which I've been covering for a long

time, there are a lot of secrets and few genuine mysteries.

He and his colleague Tim Golden have spent the better part of a year investigating those

strange incidents in Cuba that started in late 2016.

I think we have to set the context, which is geopolitical and which is the Obama administration.

Its final years undertakes this process of reaching out to Cuba and succeeding till large

extent and developing this rapprochement with Raul Castro's government and in 2016 that

really comes to fruition.

For more than half a century, the site of a U.S. president here in Havana would have been

unimaginable.

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