The next morning, everything was back to normal except Brian wasn't around. Doc had us deploying the baited barrels in deep water off the southern tip of Cape Cod, hoping to get the Great Whites during the heat of the day. The big sharks were more successful hunting seals in the morning and evening when the low light helped hide their shapes in the depths.

We'd tagged one ten-foot male, releasing him into the ocean again. "Vicki, the Captain needs you on the bridge," Leonard told me as I stowed the hose and pipe.

"On my way," I said. Today was warm and overcast, and I'd ditched the long-sleeve diving...