Tonight on the season premiere of Date Live.

Hi, this is Kate O' Markham.

She was bubbly, she was artistic, a butterfly coming out of her shell.

My dad called me and he asked like have you heard from Caitlin. I was getting worried. It was not normal.

I thought high school would be hard and then my sister goes missing.

People came out in droves.

Hundreds.

You're looking for someone in her world.

Absolutely.

You were hearing early on that there was this close group of friends.

That was the biggest part, was trying to interview everybody who knew her.

I'm extremely nervous.

I have anxiety problems.

The only thing I can tell you for certain is what they saw didn't involve me.

Proximity is not evidence of guilt.

And just because I'm near somebody does not mean that I murdered somebody.

It was a shouted like,

stop it, mmm, stop it.

I definitely heard that.

There's a big twist in this case. Another murder.

Right. There was another young woman found. They were strikingly alike.

All the elements for a killer are in this guy.

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