Up next.

It was an ambush.

Get a call for four people dead.

I like that.

But the scene yields few clues and the motive is unclear.

This case was tough.

Nothing was jumping out of it at the beginning.

Until a neighbor comes forward with a possible lead.

They see a young man and a young woman just walking down the sidewalk dressed in all black.

Would it be enough?

The families wanted answers. They deserved answers.

What amazed me as a state of secret as long as it did.

Clear Lake, Texas is a mecca for aerospace professionals from all over the world.

It includes many affluent upscale neighborhoods.

There's probably nobody in America that wouldn't mind living in these neighborhoods that are out there.

But on a July afternoon in 2003, that suburban calm was shattered.

When a teenager went to her girlfriend's house and found a blood bath.

In the living room, police and paramedics found four young adults dead from gunshot wounds.

They'd been dead for several hours.

The first walk in to your immediate left and was a female victim laying on her stomach.

You had a male victim and a female victim on a sofa.

Then behind that between the sofa and the far wall was the fourth male victim.

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