With the collapse of the motor industry, the car plants of Detroit became GeneSys’s Vattown; here, vatdivers harvest valuable biopolymers from huge vats but are forced to work in diving suits that protect them from the vats’ lethal growth medium. Even a short exposure to the growth medium results in genetic damage, whereas a longer exposure means a horrid, lingering, cancerous death. So, among the oppressed vatdiver community, sports—mutants—are common, but GeneSys will not allow the sports to work. As a result, sports like Chango Chichelski must eke out a living by petty thievery and doing odd jobs; Chango herself hopes to prove that the death of her vatdiver sister, Ada, the leader of a strike, was a company plot. She meets young Helix (Helix has fangs and four functional arms), who has run away from her guardian, Hector Martin, GeneSys’s genius scientist (he’s battling with the ruthlessly ambitious manager Nathan Graham over the future of the Tetra Project). Oddly, Helix likes the smell of the vats and seems to thrive on the growth medium that’s lethal to everyone else. It turns out that Helix is one of a new species created by Hector to work in the vats. But to survive Helix has to not only win over the angry, hostile vatdivers, whose jobs are threatened, but also help expose the murderous Graham and GeneSys itself. A well-worked-out, confidently handled drama, but lacking the freshness and flair that made Harris’s debut (The Nature of Smoke, 1996) such an eye-opener.