Mary Sue Brooks lived alone in Richardson, Texas, a northern suburb of Dallas. She owned two condos

a few doors down from each other. Sue lived in one and rented the other to her grandson and his wife.

Their one rule, which applied to both grandmother and grandson, don't come over unannounced. You may remember how Sue's friend,

Ruth, described her back in episode one. She was a happy spirit. She was a smile. She was a sunflower.

But on the evening of January 31st, 2018, Sue's family couldn't get in touch with her. Her grandson decided to break their one rule

and go check on his grandmother. When he got to her door, it was slightly open. When he saw what

was inside, he called police. Her body was laying on the floor of the living room. Plastic bags

of frozen groceries from Walmart sat on the counter, melting.

Officers called the Dallas County Medical Examiner's office and Sue's primary care doctor.

Because Sue had a blood pressure cuff sitting on a table nearby, not to mention her advanced

age, they told police they wouldn't be seeking an autopsy.

Natural causes, they said, call a funeral home instead.

But Officer Shane Harris, a 26-year veteran on the force, wasn't convinced.

Here's a clip from his body-worn camera, which was recording that night.

That's just we do one last.

And just the right shirt, like, and stay in here.

There's just one of the three playing.

You just shot on.

Harris carefully turned Sue's body over. Her body was rigid, her mouth slightly open.

But there were no abrasions or marks that suggested anything violent had happened here.

He patted down her body looking for anything clearly broken or out of place.

He didn't notice anything. He placed

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