Yes, I have an emergency. I think I have somebody dead.

Okay, and who is it? The diamonds.

Okay, and you're a neighbor or something? Yes.

Yes, I just came to check on them. They've been missing for about four days.

Oh my God. Oh my God.

They're both dead, Miss Williams. Did you find those? No.

No, okay. No, it's just one.

I don't know where to go in here.

Located on the shore of Lake Oconi, 90 minutes east of Atlanta and rural Putnam County, Georgia,

is the affluent gated community of Great Waters.

Known for its world-class golf courses, luxury resort-style amenities and million-dollar lakefront homes,

it's a popular destination for well-to-do retirees looking to live out their golden years in comfort and surrounded by nature.

It's a neighborly community where crime is rare and violent crime is almost unheard of.

But on the morning of Tuesday, May 6, 2014, a frantic 911 call comes into dispatchers from a Great Waters resident.

She and her husband have just gone to check in on their friends and have discovered a crime so horrific it's haunted the community ever since.

I'm Steve French and this is Unsolved Mysteries, Double Murder.

I was the second car on the scene. Of course, I drove as fast as I could drive from here out there about 13 miles, I guess.

Howard Sills is the sheriff in Putnam County, Georgia, a position he's held for nearly three decades.

At 10.15am on May 6, 2014, he arrives at the lakefront home of 88-year-old Russell Durmond and his 87-year-old wife Shirley.

Sure of Sills has heard the 911 call and knows he's likely walking into a murder scene.

But what he finds in the garage is a gruesome crime unlike anything he's ever investigated.

I knew something was terribly odd about this case when I realized Mr. Durmond's head wasn't there.

...