In the first volume, "Newton's Cannon," we find three key players, Isaac Newton, Benjamin Franklin and Adrienne do Montchevreuil enmeshed in the plots and machinations of the English and French kings. This is a titanic struggle over Newton's discovery of Philosopher's Mercury. It ends in the destruction of both countries when Louis XIV managed to aim a comet at London.
In the second volume, "A Calculus of Angels," the world is plunged into a new Dark Age by the cataclysm. Newton and his assistant Franklin flee to Prague, while Adrienne struggles for survival and is drawn to Tsar Peter the Great. Cotton Mather and Blackbeard lead an expedition to the Old World to find out what had happened. Along with them comes a Choctaw shaman, Red Shoes, who will play an increasingly significant part in later volumes.
With most of the players introduced book three, "Empire of Unreason," plays them out on a canvas that focuses on events in the New World. Franklin and Red Shoes lead separate efforts that bring them in direct conflict with the machinations of angels manipulating imperial Russia. These manifest as the appearance of James Stuart (the English Pretender) with an army on the Eastern Coast and the invasion of the Western Coast by Oriental and Russian forces lead by the Sun Child, who is actually de Montchevreuil's son. The plot swirls with complexities as the various characters are drawn into what may become a confrontation in the next volume. Here they fight battles and hunt the creatures of the Malakim (angels) and are hunted in turn. The writing is colorful and there is a never-ending supply of cliffhangers and twists to keep up the reader's interest.
I am reading another alternate history series at the same time, Mary Gentle's Book of Ash. This follows a young woman military commander in a struggle across the face of 15th century Europe. The two series have much in common. The heroes are facing enemies that would eradicate the human race. The primary characters are touched by magical forces that change them permanently. And their struggles are against overwhelming odds.
The series differ in that Ash is true science fiction coupled with superb military history, while the Age of Unreason is a fantasy with the illusion of a scientific basis. Age of Unreason is the more intellectually interesting, since the author takes the time to delve into philosophical and metaphysical ideas. Not in such detail that the narrative is ever the least bit tedious, but there will be times when you put the books down and think over a paragraph.
Both series are exceptional works of author's imagination that I recommend wholeheartedly. Certainly, if you enjoy one of them, you will enjoy the other.
Keyes' style is round-robin, and he rotates between characters, chapter by chapter, throughout the book. He is somewhat guilty of blatant cliff-hangerism, but I've learned to enjoy it. His characters are interesting enough that I didn't mind being torn away from one to hear about another.
But without a doubt, his strength is his masterful concoction of cultures that could have been ancestors of our own. His knowledge of native American tribes is evident, and he uses it to greater effect in this volume than in the previous two. My biggest complaint was that _Empire of Unreason_ seemed to end like a movie whose film had run out, which is why it gets only four stars. Certainly, there could've been a grander climax, but the book as a whole stands solidly.
If you've read the first two books in the series, the third is no reason to stop. My favorite still remains _Newton's Cannon_, but this book sets up a fourth (and final, so I hear) book that I eagerly await.
