“Everything okay?”

“Looks that way. My iPhone would have alerted me if something was amiss. But things are looking good. Until this series of experiments, we’d been having biocompatibility issues with the microbivores. Back when we first introduced them into our animal models, we were surprised to see some allergic reactions. Not a lot, but enough to be troublesome. When it comes to the mammals, especially the primates and humans, there cannot be any reaction. Initially we found that our subjects’ immune system could occasionally treat the microbivores as foreign invaders, which, of course, they are. Why we were surprised is because the surface of the microbivores is of diamondoid carbon, which is about as nonreactive and as smooth as can be. Are you following me?”

“Yes, sure,” George said almost too quickly. Nonetheless, Pia kept talking.

“What we deduced was that some molecules had adhered to the microbivore’s surface despite its presumed nonreactivity, leading to some level of immune response. I assume you remember all this from immunology in med school. Do you?”

“Oh, yeah. Of course!” George said, hoping to hide the fact that he remembered little of what Pia was talking about. Pia’s retention of such minutiae always impressed him. Whenever she spoke about science, her face radiated a kind of passion. She also had no trouble maintaining eye contact, which she could not do in general conversation, especially conversation involving anything personal, like emotions.

George nodded enthusiastically. He tried to think of an intelligent question, which wasn’t easy as close as they were standing together. He could smell her wonderful aroma. It was erotically intoxicating thanks to his memory of the few times they had had sex. “What kind of animals are you using as subjects for these studies?” he managed, even though his voice cracked.

“A type of roundworm, but we will soon be moving to mammals, provided these subjects show no immune response, which so far seems to be the case. I’m not looking forward to working with mammals, as you can well imagine. I’m sure you remember my feelings about that.”

George nodded again, knowingly.

“If and when you get to injecting these microbivores into human subjects—into Will McKinley, for instance—how many microbivores would be involved?”

“Somewhere in the neighborhood of a hundred billion, about the same number of stars in the Milky Way.”

George whistled. “How big a bolus would that be?”

“It wouldn’t be big at all. About one cubic centimeter diluted in about five ccs of saline. It gives you another appreciation of how small these things are. Each one is less than half the size of a red blood cell.”

“So this is what you have been working on for the last eighteen months, the biocompatibility of these microbivores?”

“Yes. It’s the main thing I have been doing, and we’re making progress. There was a breakthrough of sorts when I suggested that some oligosaccharide polymers be incorporated into the microbivore’s diamondoid surface.”

George couldn’t keep himself from wincing at this comment. Pia was talking way over his head. He vaguely remembered the word oligosaccharide from first-year biochemistry—something about complex sugars—but that was about all. To divert attention from his ignorance, he quickly said, “You mentioned back in the apartment having some scanning electron microscope images of these microbivores. Can I see them so that I have an idea of what we’re talking about?”