“Cellular hypoxia,” I said, the words slipping out before I could stop them. “A condition where oxygen is present in the blood, but the mitochondria can’t utilize it. Cyanide does that. Carbon monoxide does that.”
“We have four digital CO monitors on that floor,” Julian said immediately. “All reading zero.”
“I know,” I said.
I knelt on a sheet of plywood laid over the joists near the duct. I directed the flashlight beam down the narrow gap between the sheet metal duct and the drywall framing. The space was only about four inches wide, dark, and filled with shadows.
I brought my face closer to the gap.
And then I caught it again.
It hit my nostrils like a faint puff of warmed almond paste, artificial vanilla, and old, overheated electronics. It was stronger here than in the hallway below, rising up through the thermal bypass around the ductwork.
“Do you smell that?” I asked.
