This is not a run-of-the-mill science-fiction novel. It's science (genetics), but also more espionage thriller, in one sense, than sci-fi, and has little futuristic about it. But, what if a "good" virus could be found that would repair our bodies, instead of destroying them? And what if that could be reversed and turned into the ultimate weapon? Jack Williamson has taken these questions and built a very compelling story around them. It's hard to put down.