Tonight, we had a victim who was a 16-year-old female that had been stabbed numerous times.

I was in a complete state of shock who could do this to my daughter.

She was a good kid, somebody that everybody loved at school.

Say hi, please.

She like laughed at every single joke that I made even if they were terrible.

She made me feel special.

It doesn't happen in a small town.

There were rumors upon rumors.

Do we have a madman on the loose?

The biggest surprise was really the videotape that we found.

Unfortunately, we have the grueling task of killing our two friends.

They were obsessed with kill movies, thriller movies.

We're sick psychopaths, the naked pleasure of killing other people.

I was still waiting for her to walk out of that house.

I just remember it was a normal day.

If I would have known that was her last day, I would have treated that day different.

A young life ended by Killers starring in a homemade horror film.

I'm Lester Holt and this is Dateline. Here's Keith Morrison with a secret

here's Keith Morrison

with a secret in Black Rock Canyon.

It was Sunday afternoon calm.

No longer quite summer, not exactly autumn yet.

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