Fifteen years ago, a Charlotte woman was found shot to death on Bald Head Island. Her case has been reopened, but the mystery remains: Did Davina Buff Jones kill herself, or did someone else kill Davina Buff Jones?

The .40 caliber slug tears through the officer’s skull at nearly 700 miles per hour, shattering bone and ripping gullies into tissue.

It’s minutes before midnight, nine days before Halloween, 1999. Here, beneath the turret of North Carolina’s oldest standing lighthouse, 218 miles from her hometown of Charlotte, the officer takes her final breath.

When someone pulls the trigger on a handgun, it causes a small explosion inside the weapon. The explosion moves a piston that slams a tiny piece of metal, the firing pin, into a bullet. The force of the combustion creates pressure, sending a round hurtling through the barrel of the gun. The entire process takes just a fraction of a second.

How a pistol works is a matter of science and mechanics. It is established fact.

And it is one of the few details of Davina Buff Jones’s death that isn’t still a mystery.