Seven months after our divorce, I rushed into St. Jude’s Children’s and Women’s Hospital, still angry at my ex-wife, only to learn that she had just given birth to twin boys, and both of them were mine. Before the night was over, a nurse would place a brass key in my hand and tell me to use it before my own family arrived. And what was waiting for me beyond that was even more shocking.

Marcus pointed straight down at the stone floor near the bottom of the workbench.

“Look right here,” Marcus said softly.

One of the large slate floor tiles near the back wall was noticeably cleaner than the stone around it.

A small, recessed iron ring handle had been set right into the middle of the slate.

I reached down, grabbed the iron ring, and pulled upward with all my strength.

The heavy slate tile came up cleanly, revealing a narrow stone staircase leading down into complete darkness.

I switched on my phone’s flashlight and pointed the beam down the stairs.