I'm Lester Holt, tonight on Dateline, two women connected across time by a terrible crime.

Could one help the other?

Her roommate went looking for her because she didn't come back to the dorm.

They found her car abandoned with the keys in the ignition.

Everything was a blur. All I'm thinking is is Shannon really gone?

We interviewed her roommates, boyfriends, everybody's a suspect.

Then a phone rings in Emory, like he said,

I kidnap her, I have her.

We ran his criminal history.

That's when all the bells went on.

He pulls in, asks me to get in the car.

I feel the cold blade against my neck.

He carries me into the basement of his home.

It was jaw-dropping, just chilling.

They started digging and they found women's clothing.

It was just escalating, escalating.

There were so many victims, weren't there?

There were. There still are.

Until this guy is no longer in existence,

I won't carry this fight.

Here's Dennis Murphy with Shannon's story.

The portraits, the snapshots, the videos,

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