I'm currently working on the fourth of six books in Charles Stross's six-episode "Merchant Princes" series.* Or halfway through the middle book of the trilogy, if you purchased the most recent recombining; it seems the original set only ended up as six books when some bean-sorter decided they'd be dauntingly fat as a trilogy. (You know how us readers just hate finding a good long book to keep up the entertainment.)
Whatever. Six or three, they're great fun. I'd put off looking into them because at a glance, they sounded like fantasy and I find most fantasy unreadable, even by writers whose other work I enjoy. (Heinlein and Pratchett are exceptions and the whole Unknown magazine-shading-to-Lovecraft axis usually works for me.) I was wrong, wrong on all counts: it's not exactly fantasy, no more than Piper's "Paratime" or Laumer's "Imperium," and Stross's worlds and storyline are a fresh look at what had seemed an old notion.
The essential "one different thing" is that some people, a very few, can shift themselves and as much as they can carry to an alternate world and back again -- one world. Ours. Theirs is...different. A civilization stuck at a late-medieval level, perhaps as far along as double-entry bookkeeping and three-field crop rotation, with feudal power structures and a whole lot of peasants tilling the fields and doing the grunt work. The world-walkers, originally a single family of tinkers, have clawed their way into the aristocracy over the course of a century and a half years, thanks to their access to rapid communications, medicine, advanced weapons and so on. They're also making a fortune in our world by smuggling: it's impossible for Customs or cops to intercept goods carried, albeit by slow wagon, in a different Earth. Into this setup, Stross throws a lost noblewoman, orphaned and marooned on the Earth we know for 30-some years, who suddenly discovers her heritage.
Because he is who he is, so far the narrative has run from investigative journalism to court intrigue to action adventure, with side trips into Dynasty reruns playing on a flatscreen TV in a drafty castle dining hall, steampunk, the drawbacks of garderobes, revolutionaries under severe threat and what moving from one world to another does to one's blood pressure. Plus Dealing With Bureaucracy, something that comes as naturally to him as Stupid Diplomat Tricks did to Keith Laumer. (I think the Dynasty thing is a bit of a "hanging a lantern on it," since the series can sometimes resemble a nighttime soap opera -- one with battle scenes, misplaced nukes and steam cars, mind you.)
My only real quibble is that the our-Earth action takes place in the U.S. and while Stross does a good American accent in dialog, some Briticisms do creep in, usually in the form of turns of phrase that pass unnoticed in his home country. There's also rather a lot of firearm use, generally competently described despite a couple of minor slip-ups in the fine details (or at least terminology) of the purchase and licensing of same and their bearers. Since one of the primary POV characters is a Bostonian, such glitches are darned-near inevitable -- I don't think I understand the gun laws of Massachusetts well enough to avoid bobbles, and I have the advantage of being a firearms-hobbyist and living in the U.S. (A big problem for writers in our very-connected world is getting trivia right without veering into pedantry. Stross does this well.)
I won't synopsize farther. I don't want to spoil the fun -- and these books are fun, a complex adventure that just keeps recomplicating, cliffhangers and all. Read 'em. They're new stuff as good as the best of the old stuff.
* And for those of you concerned about excessive sibilance, an incipient lisp or a whistling upper plate, "Charles Stross's six-episode Merchant Princes series" is about as good a test phrase as you could get, even at gunpoint (which would be a damfool way to ask).
Introduction to Sim
4 months ago