Absolution Gap brings Reynolds’s complex space opera series to a conclusion.

The earlier books (Revelation Space, Redemption Ark, and Chasm City) have set up a future in which the human race has developed star-flight and colonized several nearby star systems. Advances in genetic engineering have led to a number of divergent cultures, including Ultras, who carry bodily augmentation to extremes. At the same time, some non-human species (notably pigs) have been genetically modified and their intelligence increased. A few extraterrestrial intelligences have been discovered, most of them extinct except for the enigmatic Pattern Jugglers, an aquatic race on the planet Ararat.

In Revelation Space, an overwhelming threat to all these groups entered the arena with the discovery of the Inhibitors–a machine race that is the effective equivalent of Fred Saberhagen’s Berserkers. The Inhibitors, as we learn, have a single goal, bringing destruction to all space-going civilizations. In Redemption Ark, the human race makes contact with the Inhibitors, who proceed to destroy an entire inhabited system. Barring some major turn of events, the outcome seems inevitable.

Absolution Gap follows events on two worlds a considerable distance from one another. On Ararat, a group of refugees from the initial battles with the Inhibitors waits on the home world of the Pattern Jugglers. The Jugglers merge with and eventually take over humans who swim in the planet’s oceans. Scorpio, a genetically altered pig who was once a gang boss in Chasm City, is de facto leader in the absence of Chastain, the disillusioned human who led the refugees to this world after the events of Redemption Ark. Most believe that it is only a matter of time before Inhibitors arrive here.

Light years away, on the icy moon Hela, a mad prophet named Quaiche has created a religion based on the strange periodic disappearances of the gas giant that is Hela’s primary. Rashmika Els, a young girl from an outlying village, searching for her lost brother, leaves home and joins a caravan, one of the slow-moving trains that has grown up around the religion’s central act of faith, the desire to keep the primary constantly in sight so that no disappearance will be missed. To this end, Quaiche and his followers have build huge cathedrals that travel around the slowly rotating moon, striving to maintain a position directly below the primary. Inevitably, Rashmika finds her way into the presence of the prophet Quaiche, where she slowly becomes aware that far more is going on than anyone suspects.

Reynolds brings together these two plot strands, beginning with the arrival of Inhibitors at Ararat, closely followed by the death of Chastain and the birth of a strange child, Aura, who is somehow linked to powerful vanished races. Even as an infant, she reveals her talent by giving her human guardians superweapons to deploy against the Inhibitors. She also urges the refugees to travel to Hela, where she senses the presence of a strange race that may be able to help them oppose the Inhibitors. Scorpio, the genetically altered pig, relentlessly drives the expedition, striking up an alliance with the ship’s captain, a victim of the dreaded Melding Plague that has made him literally one with his ship. Eventually the humans push Scorpio out of power, but his instincts remain accurate; when they do finally arrive at their destination, Scorpio turns out to be the only force capable of throwing a much-needed monkey-wrench into the humans’ plans.

On Hela, with its huge cathedrals slowly circumnavigating their frozen airless world, Reynolds has created one of the most compelling images in recent SF. The slow buildup to the final conflict, and the almost lapidary insertion of hints and little bits of backstory, gives the series depth to match its sweeping plot. The book ends with an epilogue that jumps into the even farther future, suggesting that perhaps Reynolds is, for the time being, done with this particular slice of future history. Yet there are enough intriguing plot strands from earlier in the history that he could certainly do more if he wanted to. I, for one, hope he does–but either way, it will be extremely interesting to see what he turns his hand to next.

Timothy Zahn is one of the more interesting writers to have come into SF in the 1980s, a versatile storyteller who’s turned out to be far more durable than some of his trendier contemporaries. Even his early work (e.g., the "Cobra" trilogy) tested the boundaries of the "military SF" subgenre. A good sample of how far he’s come is his latest. It might be called "hard urban fantasy," set in post-9/11 New York City and environs.

The story begins as Roger and Caroline Whittier, a young married couple walking home from a play at Columbia, meet a man with a gun. They are forced at gunpoint into an alley, where he shows them an unconscious teenage girl. He orders them to take her home with them for the night. Without any choice, they comply, then call the police. But when the police arrive, the girl seems to have disappeared–although there is no place she could have gone to from their upper-story apartment which has no fire escape.

Puzzled, the next morning they try to figure out what has happened; Roger even goes so far as to retrace their steps from the previous night. Then, to their surprise, the girl appears on their balcony–which the police had thoroughly searched–and asks to come inside. She gives her name as Melantha Green, but resists their attempts to learn more about her, or about the events of the previous night, although she does say that the man who led them to her was trying to help.

Now the Whittiers are thoroughly spooked. Some hunting leads them to a group of what seem to be Melantha’s relatives–although the address seems to have an inordinate number of people named "Green" living there. The Greens seem to be of vaguely Mediterranean origin, but they deftly avoid giving useful answers to the Whittiers’ questions.

Meanwhile, the Whittiers learn that their apartment is under surveillance by someone who can apparently scale sheer concrete buildings without being detected. They learn that Melantha is the focus of intense rivalry between the Greens and the Grays, who correspond closely to the Elves and Dwarves, the one group at home with forests and growing things, the other rock-dwellers and metal smiths.

Both groups tell of an ancient war that caused them to leave their homeland, which at first appears to be in the vicinity of some distant star, and migrate to New York in the early twentieth century. The well-concealed ship the Greens arrived in is still used as a meeting place and storehouse. For a long time the two groups coexisted without coming into contact. But now they have met each other, and the ancient war is about to break out again, with drastic consequences not only for the participants but for the human bystanders.

The police begin to take an interest in the events. In the post-9/11 world, vague threats of city-wide destruction take on a credibility that can’t be dismissed. By turns, the police become allies and opponents to the Whittiers, then to various factions among the Greens and Grays. Zahn’s awareness of the changed atmosphere for law enforcement gives the book an edge it would have been hard to imagine a few years ago.

Zahn does a good job of setting this plot against a realistic post-9/11 New York, making especially good use of a New York detective who decides to follow up the original visit to the Whittiers’ apartment and ends up on the front lines of the Greens’ battle plans. The focus on how the events affect ordinary people caught up in them makes this one of Zahn’s most interesting books to date.

Garcia’s latest (third in a series) follows the adventures of a trendy Hollywood agent magically transported to the era of the Wars of the Roses. The tone runs the gamut from real tragedy to tongue-in-cheek, though it’s more often in the latter mode.

As the book opens, we find Robyn Stafford moping about twenty-first century England, wishing she could return to 1461, where she is known as Lady Robyn of Pontefract, fiancée of Edward, Prince of Wales. Unfortunately, she hasn’t yet learned to travel through time at will, although she hopes her magical powers will eventually permit it. However, she manages to goad one of her rivals into banishing her and her Hollywood secretary, Heidi, back to 1461 together. They find themselves in the west of Wales, where they are immediately captured by Owen Tudor, one of Edward’s enemies.

Here Heidi’s Hollywood skills come into play, as she protects her boss from Owen’s advances by submitting to them herself. Soon, with the aid of her little bag of potent reefer, Heidi has the old Tudor under control. This is the cue for Robyn to escape to England, and after several more narrow escapes, she succeeds in finding Edward–just in time to be captured by another group of his enemies, the Woodvilles. Edward is offered the choice between marrying one of their daughters and being handed over to the Tudors–who are now invading England with a large army.

The plot continues with a series of escapes and reversals, some of which will be familiar historical material to Wars of the Roses buffs. As Robyn comes to realize, medieval politics is just as dirty as the modern Hollywood brand, but the consequences of losing are considerably nastier. The most serious complication arises when Robyn realizes that she is pregnant by Edward–at the same time as the Woodvilles are making a serious move, aided by their own potent magic, to replace her as the queen-to-be. In defense, she begins to develop her own magical powers–but will they be enough?

Garcia y Robertson smoothly mixes historical fantasy, time-travel romance, and a healthy dose of satire to create a cross-genre entertainment. This one’s a lot of fun, but one warning: the book ends on a cliff-hanger. Readers who hate waiting to find out how the story ends might want to start off by getting the first two books in the series–Knight Errant and Lady Robyn–which should be enough to keep them entertained until the fourth in the series becomes available.

Here’s one of the masterpieces of what was once a dominant subgenre of SF: the post-nuclear society. (A Canticle for Leibowitz and Wyndham’s Rebirth are other memorable examples of the trope.) At the same time, it’s a coming-of-age story and a rollicking satire. Reissued in a handsome hardcover package (touted as the fortieth-anniversary edition), this is part of Old Earth’s program to return Pangborn’s work to print. (The book was originally published by St. Martin’s Press in 1964.)

Briefly, the novel is the story of a young boy born into bond servitude in a quasi-puritanical society run by a repressive church. Restless and curious beyond his limited station in life, Davy escapes his captivity and goes wandering across the face of the world. He meets several characters who serve as mentors, one of whom eventually becomes acknowledged as a father figure–perhaps literally Davy’s father, but for that we have only the character’s say-so. For several years, he is part of a group of traveling players. We also get a glimpse of him after the main action of the story, part of an expedition that has gone in search of other lands, exiles after losing a battle to the church.

Pangborn tells the story from his protagonist’s point of view, and the tone varies wildly as the mature Davy looks back at different points of his life. At a number of points, any style-sensitive reader will be inevitably reminded of Huckleberry Finn; at others, a more restrained narrative voice presents the bald realities of a world that has somehow survived a nuclear war, and managed to rebuild itself to a pre-industrial stage.

Davy’s knowledge of his world is confined largely to the remnants of the northeastern US, primarily upstate New York and those parts of New England that have survived a worldwide rise in sea levels. Pangborn gets some fun out of playing with distorted versions of various place names, and even more fun out of Davy’s half-educated misspellings of big words. Footnotes by Davy’s companions in exile add to the feeling of multiple layers that characterizes the book’s structure.

Some of the book’s initial impact undoubtedly came from its breaking the taboos of early sixties genre fiction; the sex scenes would bother few readers nowadays, though their very presence in a "boy’s book" was a shock at the time. The prominent anti-religious theme also seems tame to someone who’s been through the subsequent decades, though perhaps there are more readers nowadays whom it would offend than there were ten years after its publication. Of course, arriving as it did just as the New Wave was gathering momentum, Davy picked up a considerable following from young readers looking for something a bit edgier than what they’d been finding in the bookstores to date.

This is the book version of a PBS "Nova" special that looks at the origins of life, the universe, and everything. Tyson, the regular astronomy columnist for Natural History magazine, is also director of the Hayden Planetarium. Goldsmith’s credentials are as a popular science writer, with a strong background in astronomy.

The authors begin with the earliest point of time scientists believe they can say anything definite about: milliseconds after the Big Bang. Most of the essential features of our universe can be traced to that unique moment, although science is at a loss to explain such fundamental facts as the predominance of matter over antimatter, or the prevalence of the undetectable dark matter and dark energy that seem to make up most of the universe.

After cooling from its primordial state, the debris began to resemble the universe as we know it. Gravity, light, and matter became predominant as galaxies and stars took shape. Tyson and Goldsmith give clear explanations of the physical processes involved. The stars, originally composed almost entirely of hydrogen and helium, gradually cooked up the other elements of the periodic table and spread them about the galaxies in supernova explosions. From these stellar ashes were formed planets and the other solid bodies that gather in the vicinity of stars.

The authors give updates on the discovery of extrasolar planets (over a hundred are now known, and the total grows almost daily). They take a critical look at candidates for favorable environments for life in our own solar system. Based on current know-ledge, Mars, Europa, and Titan may be the best candidates. The book ends with a look at the latest thinking on the origins of life, a question made much more interesting by the discovery of extremophiles–creatures that live comfortably in environments formerly considered hostile to life, such as under the arctic ice or in acid pools near volcanic vents.

This exploration of the main currents of cosmology, astrophysics, and exobiology may be the most accessible popular treatment of the subject. Be warned, though–almost all the scientific frontiers covered in the book are rapidly changing, and at best this will only bring you up to within a couple of years of current knowledge. It’s a great era for science watchers, and this book will do a lot to help you understand the game.