From the outside looking in, we were blessed. My mom was amazing. The Hargan women seemed to have it all. They lived in McLean, Virginia, an affluent town just outside of Washington, D.C.

It's a million dollar home. But as detectives would soon learn, there was a lot going on inside the Hargan household.

So in that mudroom, we discover Pamela Hansen Hargan.

She is laying on the floor of the mudroom.

63-year-old Pamela Hargan had just retired.

Now she had been gunned down in her own home. And upstairs, Pamela's youngest

daughter, Helen Hargan, lay dead with a rifle leaning against her body.

Patrol when they arrived assumed or thought that there might have been a murder suicide.

Police say Helen Hargan shot her mom Pamela Hargan before turning the gun on herself.

But for the detectives on the scene, certain clues weren't adding up.

We have manipulated crime scene in multiple places.

So what was really going on inside the Hargan home? A lot of these cases are like

huge jigsaw puzzles that you can never fully put together. A key piece of this puzzle would be a

series of 911 calls made by Helen's boyfriend from more than a thousand miles away.

I'm thinking my girlfriend's life is in danger.

Soon, another family member would be suspected.

You have got to unload this.

Blame me. That's fine.

There's nothing.

Just blame me.

In my 25 years reporting stories like this, the Hargan case is one of the few that sounds like something made up by a Hollywood screenwriter.

A story of betrayal you would struggle to believe if it wasn't true.

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