...well, it's three books, collectively called the Baroque Cycle.
I can't even begin to describe this epic, three-volume, genre-bending story.
Somehow, Neal Stephenson manages to blend the birth of the scientific revolution, the birth of capitalism, and swashbuckling action into a massive, multi-faceted, intricate tapestry. It's actually six novels, interwoven across three volumes.
The story follows several major characters. One is Daniel Waterhouse, a roommate of Isaac Newton's, who participates in some of of Newton's major discoveries and who witnesses Newton's long-running conflict with the German mathematician Leibniz over who invented calculus. Sound boring? It's not! Waterhouse is also present for early attempts to invent computers, sceintific intrigue and competition that involves Edward Teach (Blackbeard) of all people, and various fires, plagues, and revolutions. Interwoven into Waterhouse's story is the tale of two rogues - "Half-Cocked" Jack Shaftoe, King of the Vagabonds (perhaps my favorite fictional character ever), and Eliza, a girl he rescues from a sultan's harem. They range across Europe, tangling with witches, insane French nobles, slavers, and pirates with a penchant for anal rape (quote: "Good Lord, that's an apocalyptic buggering!"). Eliza, much brighter than most of the men in the story, manages to almost single-handedly create our modern capitalist system, while Jack - unable to consummate his love for her due to an unfortunate injury that gives him his nickname - does his best to protect her. Shaftoe also becomes embroiled in a quest for King Solomon's gold, which brings him into the same sphere as Newton, who believes Solomonic gold has semi-mystical properties. The story never quite enters full-on fantasy territory, but it flirts with the fantastic at every step. Again, there is so MUCH of this story that it's difficult to summarize - all I can say is trust me: this is great stuff.
One aspect of the story that is vaguely fantastic is the character Enoch Root, who appears on and off throughout the tale at times of crisis. This is not all that strange, in and of itself. But in Stephenson's previous book, Cryptonomicon (a story about codebreakers in WWII interwoven with stories of computer nerds and underwater salvage - yeah, you kinda have to read it), Enoch Root is also a character. So, seemingly, this guy is immortal, and is equated with the Biblical Enoch. This is never heavy-handed or religious, and the signficance of the Enoch Root character isn't quite clear. He does seem to be connected with Solomonic gold, which is also featured in Cryptonomicon (the characters in Cryptonomicon have the surnames Waterhouse and Shaftoe, indicating they are descendants of the characters in the Baroque Cycle).
Stephenson is probably my favorite writer, and I'm about a fourth of the way through his latest novel, Anathem (a play on words between "anthem" and "anathema"). More blatantly sci-fi, it's quickly shaping up to be every bit as good as the Baroque Cycle or Cryptonomicon. Stephenson's earlier books like Snow Crash are pretty much standard cyberpunk fare. With the Baroque Cycle, he took a quantum leap forward, creating the most intricate, complex, fun-to-read novel I have EVER read. EVER. Do yourself a favor and check it out.