Bios opens as the body of Zoe Fisher is prepped for transmission to the distant solar system containing the planet Isis. A technician rebelliously disables a device in Fisher's body that controls her emotions and ensures her loyalty to the Earth-based Families, which control the research effort. This sets up the intriguing background to the story. In this future, Earth, devastated by plagues, is under the draconian control of several "Families." The Family control extends to reproductive rights, and indeed their most trusted servants are castrated to remove that distraction. The rest of the Solar System is independent of Earth, consisting of a Mars colony and an individualistic set of Kuiper Belt colonies. The two factions are collaborating somewhat uneasily on the research effort at Isis. Most of the novel is told from the point-of-view of three people: Kenyon Degrandpre, the castrated functionary who runs the Isis Orbital Station; Tam Hayes, a Kuiper native who runs the major on-planet research station; and Zoe Fisher, a clone who was engineered by a faction of the Earth Families to have much greater resistance to the dangerous "bios" of Isis.

The story proper begins as Zoe arrives at Isis Orbital Station. Her arrival coincides with the first of a series of on-planet catastrophes. It seems that the native organisms are getting better and better at breaching the various security barriers humans have placed about their different research stations. As even a single breath of Isis' air will kill a human horribly in hours, this is very disturbing. Zoe Fisher's new equipment, both external and internal, is intended to be a step in increasing human ability to explore Isis, but is she too late? And what is her real purpose? Kenyon Degrandpre fears she is a tool foisted on him by the rival faction that developed her. Tam Hayes fears he is falling for her, and doesn't know if he can bear to put her at risk. And Zoe wonders why her emotions and memories are so different now, and why she is no longer sure of her own purpose and loyalty.

This is a short book, not much over 60,000 words, which is a nice contrast to many of today's novels. In this brief space, Wilson stays focussed on the arc of the disaster facing the research station. The hints of the background culture are fascinating, but I think Wilson chooses well to leave the hints as just hints. His real purpose is to tell an exciting story of a desperate battle against an unremittingly harsh environment, and then to advance a somewhat mystical explanation for the conditions on Isis and on Earth. The story is a good read, and the ending, purposely left a bit open, is thought-provoking. It falls a bit short, however, in emotional impact. We don't have the time to really get to know the main characters, and as such, the resolution doesn't grip quite as strongly as it might have. The novel's theme, also, while thought-provoking, is just a bit too lightly sketched. I wasn't quite convinced. Nonetheless, I enjoyed Bios. It's not as good as Darwinia, but from my point of view, that's praising with faint damns. Wilson is one of our most exciting and versatile writers, and if this is middle-range for him, it's still very good.