The Gurus came in peace, bearing gifts.
They were a highly advanced, interstellar species who brought amazingly useful and sophisticated technology to the human race. There was, of course, a catch. The Gurus warned of a far more malevolent life form, beings who have hounded the Gurus from sun to sun, planet to planet, across the cosmos. Pundits have taken to calling them the Antagonists - or Antags - and they have already established a beachhead on Mars. In exchange for all they've done for us, the Gurus would now like our help.
Enter Master Sergeant Michael Venn, a veteran Skyrine (a Marine who is specially trained for off-world combat) who is dropped onto the Red Planet with his band of brothers on a mission to take down as many Antags as possible.
But from the moment they're dropped through the thin Martian atmosphere, their mission goes horribly, terribly wrong. From a group of female special ops Skyrines with secret orders, to mysterious humans who've settled on Mars, to the overwhelming and highly-reinforced Antags themselves, Venn and his brothers will face impossible odds just to survive - let alone make it home alive.
Stuffed with adrenaline-pumping action and mystifying ambiguity, Bear's series launch is a tempest of rousing SF adventure with a dash of Peckinpah. On a near-future Earth, the alien Gurus have shared technological advances in exchange for military aid in combating the Antags, who have pursued them as far as Mars. Sgt. Michael Venn and his squad of high-tech Skyrines are sent in on a vaguely defined, shoddily planned mission, which has them dodging poison darts and falling comets until they are stranded, wounded, and running out of air. Rescued by a splendidly terse settler, they seek cover in what at first appears to be an abandoned mining operation, but soon the labyrinth, called the Drifter, emerges as the motive to the conflict itself. Eerily and often gloriously explored but scarcely explained, the Drifter is a bonanza of seemingly unlimited resources that both the Gurus and the Antags are inexplicably seeking to destroy. A psychedelic mind-meld with the structure itself adds a layer of complex mystery, but a dead-stop ending leaves Venn and Bear's readers to impatiently await word of what it was all about.
Starship Troopers by Robert Heineken meets the Halo milieux is my best attempt at describing this. Personally love majority of Greg Bears work - especially the early stuff - this perhaps falls in the middling category I think. Style perhaps triumphing over content. Characters are a little two dimensional and I felt they might have been developed more. However it's a good read and has plenty of pace. Suspect there will be sequels as the plot line leaves many threads to follow up on.