We did one last inspection of our gear as we approached the dive site. The divemaster pointed out the hazards, asked if we had questions, checked our gear, then let us hit the water. Adrienne and I went on air, checked our masks, set our dive watches, and let ourselves fall back into the warm Gulf waters.

As soon as I was under, I felt alive again. Staying next to my dive buddy, we kicked down to the sand bottom near the bow of the ship. The only thing I could hear was the bubbles from my breathing, and the sounds of boats driving by.

The next thirty minutes were...