Timothy Zahn is one of my favorite authors, so I had high hopes for this book quality-wise. Didn't know what it was about ahead of time, was just looking for something to do w/ my Nook.
This is a sci fi book, but without the pew pew. There's a planet, Triplet, so named because it's actually 3 planets in one! Who built this system, how does it work, and why did these aliens (it must be aliens, right?) populate the 2 "inner" planets w/ humans? None of this is explained because no one knows. The "tunnels" between planets keep all technology out, including clothes, so you arrive naked in the middle of nowhere, hoping for the best. The natives of the two inner planets, Shamsheer and Karyx, know nothing about the other worlds. They certainly don't know they're being visited by the outside galaxy! Human explorers do their best to explore w/out alarming the locals, but they're not making much headway. How does the technology on Shamsheer work? No one knows, it's all self-repairing, self-regulating, intelligent machinery that violently resists attempts to study it. How does the magic on Karyx work? No one knows, it's all sprites and spirits and djinns and demons, and they do not deign to stick around and talk to the humans who summon them.
The main character is a whiny, immature college student w/ severe daddy issues... no one's idea of a likeable heroine. Figured the guy who wrote Leia, Winter, Mara Jade, etc so well could do better, but whatever. It's annoying, but the exploration of the 3 worlds leads into the mystery smoothly enough. And once the main character and her guide realize they are in serious danger, things get tense enough that I had no choice but to keep reading.
Zahn is a master of world-building, and it shows. I've yet to see a better example of Clarke's 3rd Law: any sufficiently advanced technology is indistinguishable from magic. I don't know how to explain the mystery without giving away too much. Suffice to ask: if you knew Skynet was plotting something, but you didn't know what, and you didn't know who Skynet was much less what a computer is, how would you stop it? At some point, forget stopping it, how do you survive??
This is a straightforward, fun thriller; you not be be part of a specific fandom or be up to date on continuity to enjoy it.