“I need a closed air system and a hood,” I explained to her.

“Come on back.”

A long sloping hallway always polished bright led to a series of glass-enclosed laboratories. Inside, scientists were prepossessed with pipettes and gels and radioactive probes as they coaxed sequences of genetic code to unravel their identities. Wheat, who battled paperwork almost as much as I did, was sitting at her desk, typing something on her computer. She was an attractive woman in a strong way, forty and friendly.

“What trouble are you getting into this time?” She smiled at me, then eyed my bag. “I’m afraid to ask.”

“Possible product tampering,” I said. “I need to spray some on a slide, but it absolutely can’t get in the air or on me or anyone.”

“What is it?” She was very somber now, getting up.

“Possibly a virus.”

“As in the one on Tangier?”

“That’s my fear.”

“You don’t think it might be wiser to get this to CDC, let them . . .”

“Douglas, yes, it would be wiser,” I patiently explained as I coughed again. “But we haven’t got time. I’ve got to know. We have no idea how many of these might be in the hands of consumers.”

Her DNA lab had a number of closed air system hoods surrounded by glass bioguards, because the evidence tested here was blood. She led me to one in the back of a room, and we put on masks and gloves, and she gave me a lab coat. She turned on a fan that sucked air up into the hood, passing it through HEPA filters.

“Ready?” I asked, taking the facial spray out of the bag. “We’ll make this quick.”

I held a clean slide and the small canister under the hood and sprayed.

“Let’s dip this in a ten percent bleach solution,” I said when I was done. “Then we’ll triple bag it, get it and the other ten off to Atlanta.”

“Coming up,” Wheat said, walking off.

The slide took almost no time to dry, and I dripped Nicolaou stain on it and sealed it with a cover slip. I was already looking at it under a microscope when Wheat returned with a container of bleach solution. She dipped the Vita spray in it several times while fears coalesced, rolling into a dark, awful thunderhead as my pulse throbbed in my neck. I peered at the Guarnieri bodies I had come to dread.

When I looked up at Wheat, she could tell by the expression on my face.

“Not good,” she said.

“Not good.” I turned off the microscope and dropped my mask and gloves into biohazardous waste.

The Vita sprays from my office were airlifted to Atlanta, and a preliminary warning was broadcast nationwide to anyone who might have had such a sample delivered to him. The manufacturer had issued an immediate recall, and international airlines were removing the sprays from overseas travel bags given to business and first-class passengers. The potential spread of this disease, should deadoc have somehow tampered with hundreds, thousands of the facial sprays, was staggering. We could, once again, find ourselves facing a worldwide epidemic.