One of the most famous quotes in science fiction comes to us courtesy of Arthur C. Clarke: "Any sufficiently advanced technology is indistinguishable from magic." At first read, Howard V. Hendrix's Empty Cities of the Full Moon seems to exemplify Clarke's Law, but in truth Hendrix goes deeper than that: technology is magic, with all its mystical underpinnings and sense of awe intact, while magic is technology, with its rigorous R&D requirements and painstaking development. They are merely different ways of describing reality, of seeking to grasp and manipulate the true wonders inherent in the human mind, thereby fulfilling our vast potential. And not only our potential, but the potential of our universe, since we are our universe in holographic miniature.

Heady stuff, yet the potential of the human mind is a subject Hendrix returns to again and again; first in his enjoyable Lightpaths trilogy, and now in Empty Cities, which might be considered the fourth book of that trilogy. Hendrix begins by marking the point where the universe of Empty Cities splits from that of the Lightpaths, and employs as one of his main characters a previously minor character, John Drinan, who was transported to a new universe by a cataclysmic event that occurred in the course of the earlier books. Despite these interconnections, knowledge of the trilogy is not necessary. A good thing, too -- you may have a hard time juggling all the ideas Hendrix tosses around in just one book.

In alternating slices from two different time periods, Hendrix shows the outbreak of a horrific plague and, thirty-three years later, the tiny remnants of the world's human population and their struggle to survive. The plague is no ordinary disease: it is a highly-contagious, man-made madness caused by artificial prions, called prionoids. Originally designed to alleviate mental illnesses by controlling the levels of such naturally-occurring brain chemicals as endorphins, enkephalins, and serotonin, the prionoids backfire instead, triggering disastrous folds in their target proteins. Like an origami figure one crease away from a lovely crane that somehow, when that last fold is made, comes out as a nightmarish chimera, the renegade prionoids fold and refold the human mind through a series of four epidemics of insanity that slowly begin to include not only psychological, but physiological changes, the last of which is the ability to shape-shift into feral, animal-like creatures, a stage that almost always ends in death.

Befitting this plague, the survivors are no ordinary humans. Calling themselves Tru-Folk, a small enclave in the Bahamas has not only preserved pre-plague technology, but also enjoy the fruits of immortality treatments. They've created a race of bio-engineered Mer-Folk -- mer-men and -women who guard the islands from the rest of humanity's orphans, the so-called Wer-Folk who have been touched by the plague and forever changed.

The Bahamian enclave is led by Cameron Spires, a biotech billionaire who established the enclave during the dying days of Earth's civilizations. He brought with him the best and the brightest, many of whom were involved in the plague's onset, such as the aforementioned Drinan. The enclave also includes Tomoko Fukuda, whose biotech company created the original prionoids, and her ex-husband, Simon Lingham, an epidemiologist with the World Health Organization who was the first to link the massive outbreak of aberrant behavior to a contagious pathogen. In addition there's Sister Vena, a nun charged with caring for victims during the original outbreak, who has grasped the sociological and psychological underpinnings to the physical changes wrought by the plague; and Mark Fornash, the first to recognize in the behaviors something very old and deep, powers that were lost as the language-using, tool-building human brain took shape.

Spires surrounds himself with these brilliant people as civilization falls apart, but they do not remain. Spires seems too committed to the status quo, too vindictive in his treatment of the remaining plague victims, too comfortable with ignoring the questions that have never been answered -- what really caused the plague and how can it be cured? What is the explanation for the seemingly paranormal events surrounding plague victims? Is peace between the Tru-folk and the Wer-folk possible?

During the 33 intervening years, Spires' brain trust leaves his safe haven one by one in search of answers to these and other questions. Simon Lingham, the last of the group, secures the freedom of a Wer-woman captured during a raid of the enclave by the Wer-folk -- but at the cost of his own standing in the community. Exiled, he leaves the island, setting in motion a chain of events that draws together old comrades and new in a journey north along the devastated Eastern Seaboard toward the ruins of New York City and a date with transformation and transcendence.

Hendrix has never shied away from big ideas. Yet at the heart of this and other works is an uplifting message -- the synergistic connection humans have with the universe around them. Intelligence -- with all its varied connotations of thought, of awareness and self-awareness, and of reason -- matters to Hendrix. Even the intelligence of his readers matters, as Hendrix also doesn't shy away from making us work to understand the issues as his characters discuss, expound, debate, and occasionally lecture.

Unfortunately, in his efforts to stimulate our brains Hendrix has created some noticeable chunks of exposition and some rather obvious set pieces. Places where another writer might have taken the opportunity to delineate character, move the plot along, or sharpen the setting, he often fills with more ideas. And the ending flounders a bit -- Hendrix has thrown so many elements into the mix that pulling them all together at the climax proves to be just beyond his reach.

But dammit! Hendrix has an idea. Several ideas, really, and good ones. He wants us to understand, asks us to think. If you have any intellectual leanings at all, you'll find this a worthwhile read. I, with my dull job and my hum-drum, middle-class life, appreciate being asked and look forward to the next time he makes my brain hurt.

Lori Ann White is a writer and martial artist currently living in the San Francisco Bay area. She has appeared in Writers of the Future, Vol. 3, Full Spectrum, Vol. II, and has work forthcoming from Asimov's Science Fiction. She is also personally acquainted with author Howard Hendrix, and finds him as charming and challenging in person as he is in print.