First of all, ignore most of the blurb on the cover. The Descent is nothing like you might expect if you simply brushed past it on the shelves. It is, fortunately, significantly better. Having said that, it isn't quite as good as it thinks it is, but given that it's written by the man who wrote the abominable Stallone vehicle Cliffhanger for the cinema (it says here, minus the abominable vehicle bit) that it's readable at all should be regarded as something of a triumph.
Enough skirting about the issue though; imagine if you will that the old "Hollow Earth" hypothesis (one which has been left languishing for nigh on a century now, even by sf writers, so is surely well overdue for a revival) turns out to be at least partially true. The Earth's crust is riddled with over a million miles of tunnels stretching down to unimaginable depths, most of which are inhabited, just barely, by a whole host of savage and dreadful-seeming creatures. Arguably of more importance however, the tunnels reveal and give access to staggering new mineral deposits and conceal untold historical treasures from the dawn of time, the latter hoarded by underground dwellers called "Hadals", an offshoot of sorts of our very early ancestors.
Government and big business both rush in to exploit these treasures, sending expeditions that trample and are trampled in turn by the Hadals, who have been the inspiration for all our myths and legends about demons. But there is something odd going on underground, and before you can say "Dr Faustus!" the race is on to find the hypothetical leader of the Hadals, who is on a mysterious mission of his own. If I tell you that there's just a wee bit of religious allegory involved you can guess his name for yourself.
The Descent is a curiously jumbled concoction. The encounters with the Hadals are extremely well managed (especially since they are for the most part only glimpsed, and Long is surprisingly proficient at writing Horror) with an odd sort of literary scientific detachment, and so are the descriptons of modern technology. To be fair this isn't straightforward techno-fetishism, Longs' attitude to our tools remains more or less ambivalent. In this repect the writing is similar to Michael Crichton (thanks to the writer of the dust jacket for pointing that out) and like Crichton, Long always seems to be consciously trying not to write sf - one of the characters throws away his useless stolen maps of the underworld at one point, saying "Good riddance. Nothing but science fiction."
It's a shame because if Long had been less concerned with trying to be "Arty" The Descent would have been a better book. Self-consciously using such an unlikely assortment of adjectives ("daedelian" was my personal favourite, but there are any number of other horrors in the first chapter alone) the book wears its' thesaurus not so much on its' sleeve as nailed to its forehead.
It may be that some of the odder encounters with the Hadals, which are interspersed throughout, simply don't work very well, jarring rather badly within the books' narrative structure, most of the characters are entirely unsympathetic, Hadals and humans alike, but oddly enough I enjoyed reading The Descent. Jeff Long has done a lot of homework, and if at times he's too keen to show just how much then be thankful he has an eye for the more bizarre and compelling elements of nature, not just its facts and figures.
Go and read The Descent, it's a dark and interesting book. Then write to Jeff Long to tell him what a great piece of sf you thought it was. He'll thank you for it, I'm sure.