We must warn you that today's episode contains graphic descriptions that may be disturbing or triggering to some.

We will warn you as we approach those sections, but discretion is advised.

I was trying to look at her lips like I'd do my son and she was wording help.

They were vicious.

I just helped.

They were cruel.

Or call for help.

They inflicted all this harm for their own pleasure.

What do you think she meant?

They felt in control.

I don't know exactly.

They kind of got into a group mentality of let's all have this rage.

But I know my mind if I was in her state calling for help.

And this was the ultimate betrayal.

You witnessed her getting lit on fire?

Yeah, parts of the lit on fire, yes.

I'm Scott Weinberger, investigative journalist and former deputy sheriff.

I'm Anna Siga-Nikolazi, former New York City homicide prosecutor and host of investigation discoveries through conviction.

And this is an anatomy of murder.

If there's one word that would describe today's story, it is dark.

There is a sadistic quality to this crime not often seen.

For today's case, we interviewed Deputy DA Denise Yokem.

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