How does anybody look at somebody drown and not help them?

How do you do that?

They found a boat.

Mike wasn't in it.

We thought maybe he's had an accident.

The thought is the alligators have eaten Mike.

Something don't add up.

People don't just disappear.

There was an affair happening for years.

I'm telling you, you don't mind

when you was a good to you.

That is just a whole other level.

A chilling confession and a crime

almost too cruel to be true.

I'm Lester Holt, and this is Dateline.

How be... I'm Lester Holt, and this is Dateline. Here's Dennis Murphy with Secrets of Lake Seminole.

Lake Seminole, an hour outside Florida State Capitol, is deep south.

Fishing hunting country was Spanish moss on the oaks.

In season, the duck hunters are out before dog.

And it was there in the year 2000 on a December morning,

an experienced outdoorsman named Mike Williams went duck hunting.

It was the 30-year-old hunter's sixth wedding anniversary, and there'd be a stay at a romantic B&B that evening. But the morning hours were his to hunt. That was his outlet. That was what he

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