At first, Dane Nilson appears to be a talented—if somewhat single-minded—botanist, a quiet genius whose job is maintaining the station's massive hydroponics facility. Though he helps Anhi unwillingly, she cannot help noticing that once his mind is made up, that assistance is very effective. As the two begin to trust each other, it becomes apparent that Dane is well connected, politically active and a big player in the movement for space station independence.

Dane's organization is politically radical but has taken a cautious approach in its dealings with an Earthbound culture that sees the space platforms as subservient colonies at best and looming threats at worst. He and his followers have been inching their independence agenda forward steadily, but now outside agitators are causing tensions to rise, starting anti-Earth Internet rumors, provoking fights with tourists and dragging the issue into the media in the most volatile ways possible.

Soon enough, Anhi and Dane detect connections between her quest for vengeance and the infiltration of New York Up, but their opposition is shadowy, well prepared and ruthless. The unlikely allies must figure out the enemy game plan—and soon, because whoever it is has learned what Dane is hiding: He has committed the one crime in all of Earth and space that still carries the death penalty!

Intrigue and murder in zero gravity

Mary Rosenblum's Horizons is a taut and suspenseful thriller, an intriguing hunt and chase that takes Anhi to a world that barely seems man-made. The story's parallels with colonial history are unmistakable, and yet this is no mere transcription of the past: The people of the space stations are in the process of creating a future as different from groundside society as the vacuum of space is from Earth itself.

The author's carefully constructed plot is as intricate as any chess game, which should please readers who enjoy cloak-and-dagger storylines. Though it bogs down somewhat in the middle, the payoff is worthwhile, and the book ends on a genuinely satisfying note. Anhi is an appealing heroine with some unique family baggage, and it is enjoyable to watch her relationship with Dane unfold ... though fans of romance may find this one to be somewhat slenderly developed.

The real joy of Horizons, though, lies with watching Anhi fumble around New York Up, meeting its various colorful characters, earning their trust and puzzling out the dynamics of the space-dwelling community. "The Can," as its residents call it, is a vibrant and fascinating place, one of those science-fictional settings that is so fully realized that a reader may reach the end of this novel and be surprised to realize that, as yet, this space platform exists only within the imagination.