Blood Music — Greg Bear

THE SMALLEST OF ORGANISMS.
THE GREATEST OF TRANSFORMATIONS. SO BEGINS TOMORROW...

VERGIL ULAM was the genius behind "biologic": the restructuring of cells. Cells that can think. When Genetron canceled the project, Vergil smuggled his life's work out of the lab the only way he knew how: He injected himself with them.

At first, the effects of the "intelligent" lymphocytes were small miracles. His eyesight, his overall health, even his sex life, improved.

But now, something strange is happening. Vergil's concocted cells are capable of forming complex organisms and eventually whole societies in his blood and body. He carries a universe within himself. A universe of cells. Intelligent cells.

And they think it's time for a change...