The last of the gypsies, the crew of the generation ship called Star Road knows better than to expect a warm reception when it returns to Earth. Having left thousands of years before, they were unfairly blamed for spreading a devastating plague. Now, however, they have nowhere else to go. Radiation-induced infertility is decreasing their numbers. Their only hope of long-term survival is to petition their homeworld for land on which to develop a colony.

Even by their modest expectations, though, the Earth that greets them is an ugly shock. The planet is all but covered in a crystalline substance known as Ice, a human-made data storage medium which is growing out of control. When Star Road arrives, Ice is just weeks from overgrowing the last patches of ocean and land. Humans settlements are sparse and primitive, surviving in the buried cities like Vancouver and Seattle and mining what remains of their resources.

Dismayed at their findings, the people of Star Road turn to their Ship Mother, a woman who was cryogenically frozen at the beginning of their voyage to act as a receptacle of their history and traditions. Zoya Kundara sets out to establish diplomatic relations with Earth's one remaining power, a woman-led group of atheists whose traditions are borrowed from those of Catholic nuns. The Ice Nuns, as they are called, are determined to break the encryption which protects Ice's data. They are less eager to deal with off-worlders whose grasp of technology may exceed their own, and almost immediately their Mother Superior sets to work on undermining the ship's captain and pushing the Star Road toward mutiny.

Their hostility leaves Zoya with no options but to crack Ice's encryption herself, finding a way to stop its advance before her people's hoped-for refuge becomes a lifeless databank.

An Earth made genuinely alien

Kay Kenyon's Maximum Ice is a knockout adventure which sprawls across a thoroughly altered Pacific Northwest landscape. Ice has covered the West Coast so thoroughly that the sea corridor to Vancouver Island is now a land route, suitable for sledding. As Zoya pursues her mission, she moves through lands that merge familiar geographical features with new ones. Error's Rock, for example, is a massive structure dedicated to the data-processing paradox which is driving Ice's deadly growth.

Kenyon has also dotted her terrain with vicious packs of rats, as well as the occasional snow witch. These modified humans have partial access to Ice's information, but the price is steep—they survive by eating human flesh. But while the surface is perilous, it is no match for the human enclaves, where one sees the real hazard in this new world is its most ancient one, human treachery. The machinations of people—the leaders of underground cities, the Star Road's divided crew, and the faction-split Ice Nuns—are the largest threat to Zoya's safety.

Novels about quick and sudden disasters showcase the best and worst of human nature. In allowing Ice to spread for centuries before the ship's arrival, Kenyon has evolved an entire culture around a slow-burning emergency. This gives her scope to take evil to big extremes in Maximum Ice, creating a setting where cannibalism and child-selling are daily events. Over the centuries, though, this society has ground away its capacity for humane behavior. The forces of good are thus somewhat outshone in this book—its few heroes carry the battle more by virtue of superior courage and religious faith than anything else. It is a rosy outcome, but one that contrasts somewhat with the dark view of human corruption built up through the novel.