I wasn't sure what to expect from the first novel by Adam-Troy Castro that hasn't been some sort of media tie-in. What a surprise to discover a storyteller with just about the bleakest vision of humanity's future one could imagine. "We're all owned," declares one character in a line that singlehandedly sums up this novel's sense of cynical resignation, "it's just a matter of deciding who holds the deed."

In the future imagined by Emissaries from the Dead, humanity (as well as members of a myriad of sentient races) are mostly vassals, their many worlds run by governments or corporations or religious and political ideologies to whom the people must indenture themselves, putting up their own futures as collateral. Be a good little servant for so many decades, and you just may earn freedom and a happy retirement on down the line — provided you don't screw up and get booted back to square one. And lording it over everyone are the ineffable AIsource intelligences. Of ancient and unknown origin, these distributed artificial entities are, for all intents and purposes, just like gods. They interact with people freely, but what they could possibly be getting out of such interaction is shrouded in mystery.

What impresses about the book, and helps it rise above the sense of pessimism that quite honestly can feel overbearing at times, is the surprising degree of both structural and thematic complexity Castro brings to a plot that starts out as your typical noirish detective story. One One One is a cylindrical habitat in interstellar space created by the AIsource. They have populated this little experiment with at least one engineered sentient race, a kind of sloth called the Brachiators, who inhabit the Uppergrowth, a delicate zone high up in the habitat's ecosystem, below which lurk kilometers of noxious high-pressure clouds and some kind of fearful toxic ocean. It's not a good place to be if you're afraid of heights. And a fear of heights is among the least of Andrea Cort's neuroses.

Cort is an investigator for the Judge Advocate of humanity's Diplomatic Corps. She has been sent to One One One in the wake of the murders of two of its human inhabitants. When the AIsource made One One One and the Brachiators' existence known to the rest of civilized space, concerns were immediately raised that the AIsource were engineering slaves or something, and to mollify those concerns, the AIsource have allowed a team of humans from the Dip Corps to study the curious, slow, yet undeniably intelligent creatures. Now two of those humans have been killed in ghastly ways, and Cort is under explicit orders to steer her investigation away from their AIsource hosts. Logically, they are prime suspects. But if they are guilty — a conclusion that seems both clear and hopelessly illogical — it could cause a major diplomatic nightmare. After all, how do you declare war against an enemy that's so godlike — all-powerful, omnipresent, yet intangible?

Andrea Cort's investigation will lead to secrets she never imagined, and Castro has fun misdirecting us and tossing off red herrings like all good mysteries should do. Cort herself is antisocial to the point of misanthropy at first, and we know going in of a horrendous ordeal she suffered in her childhood that has caused even her to think of herself as a monster. Nothing is more clichéd than the jaded, world-weary detective with a checkered past and a chip on his shoulder. But Castro gives Cort some real trauma to overcome. And as Emissaries unfolds (the book's title is a reference to the curious realtionship the humans have to the Brachiators), it goes far beyond the boundaries of a simple whodunnit/cop story, and becomes mostly about Cort's personal journey towards healing and saving herself. She's a tough nut to crack, but ultimately (and with the help of a few allies among the supporting players we also come to admire), she's one of SF's most sympathetic and courageous heroines, simply because what she's endured in her life would be nearly impossible for almost anyone to survive with any semblance of sanity.

The book is on slightly shakier ground when, later on, Castro plays around with the theme of free will versus omniscience. It isn't badly handled, it's just that you're left with the impression Castro is saving most of the meat there to stew for a sequel. And it's also true that, at times, he slips and falls into the kinds of expository traps that ensnare so many crime fiction writers. Solutions to baffling mysteries are commonly laid out in marathon monologues by Cort.

But on the whole, I think most of you will find this a uniquely absorbing read. It envelops you in a truly exotic and alien environment, and gives you a heroine to root for precisely because her voluminous character failings are genuinely tragic, not merely some kind of contrived aggro chic. It offers mystery, action, a few good jolts, and a bit of the old redemption sans mawkishness. All the ingredients for a story sure to knock 'em dead.