This is Planet Money from NPR.

Kevin Montgomery is a corn breeder.

He selects and grows corn in order to make new varieties.

Back in July 2012, his main gig was helping out a big international company with this kind of work.

But on the day in question, Kevin was at home in his own farm field in rural Illinois.

It's one of the hottest days of the year.

And he's been outside, tending to his corn.

I was setting up plants for pollinating.

I'm already dripping wet with sweat.

I come into the house, I get a glass of lemonade,

and while I'm standing, drinking an lemonade in front of the refrigerator with the doors still open,

my wife Kathy says, are you expecting any visitors?

Kevin says, no.

And his wife says, well, there's a black SUV coming up the driveway.

I don't know anybody with a black SUV.

The black SUV stops, the driver cuts the engine.

Gentlemen get out of the vehicle and they're both wearing sport coats.

So that in and of itself is unusual.

Kevin, he's wearing a plaid shirt with a sleeves ripped off.

They show me their badges. They say we're from the FBI. They give me their names.

Kevin offers them lemonade. They refuse.

They are apparently not allowed beverages of unknown origins.

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