The Culture series can always be counted on for showing Iain Banks' writing at its best and the Hydrogen Sonata proves to be no exception to the rule. If we haven't really had the full-on science-fiction ideas combined with explosive action experience since Excession, the series thereafter has shown a certain maturity, slowing down the pace to consider philosophical and metaphysical questions brought up in that book relating to the Other Side, on questions of Life, Death, Oblivion and the nature of what lies beyond the material world. Those questions are to the fore again in The Hydrogen Sonata, thoughtfully considered and brilliantly interweaved into the whole culture of the Culture, but happily Banks' writing and the plot surrounding the story is once again at a dazzling level of wit and brilliance that we haven't seen from this author for a long time indeed.
You might not expect that from the initial premise, where yet another civilisation, the Gzilt, have reached that stage in their evolution where, tired of existing with the mundane realm of matter and energy, they've made the collective decision to Sublime, crossing over to that indefinable place (between the seventh and eleventh dimensions we discover here) where all advanced cultures and civilisations eventually accede and effectively retire. Some are surprised that the Gzilt have decided to make the big jump at this stage in their development, but with only 23 days left until the Instigation, many have already crossed over, leaving only a small remainder of their people to take care of the final ceremonies and housekeeping formalities, fending off Scavenger races and generally dealing with any last minute business that might crop up. Inevitably, one ship turns up with a big surprise for the Gzilt, and suddenly chaos erupts. The ship Minds of the Culture, and undoubtedly Special Circumstances, are of course very interested in the rumours that abound around the incident and send ships in to observe the final frenetic days of the Gzilt.
Well, "observe" is of course a vague and rather passive term for the inquisitive intervention of the Culture, and of course it involves them gathering intelligence, searching for certain artifacts, transporting and in some cases reanimating stored individuals who might be able to satisfy their curiosity. If I'm totally honest, there's nothing new in this - there's a lot of running around and a lot of confusion where you aren't quite sure what's going on sometimes, the usual conspiracies, bad guys and big secrets which may or may not prove to be anything more than a red herring (I hate it when he does that), and some usual gung-ho intervention - sorry, observation - from the Culture ships and SC operatives (presumably, but who knows?), with an innocent - usually female - figure caught up in it all. It doesn't matter in the slightest when Banks has a concept as good as that of the Culture to play around with (if you haven't read a Culture book before, it won't matter either, because the author sums up the ideas concisely very early on, before getting straight on to business with little formality) and when his writing is as polished and witty as it is here, principally in all forms of interaction between the characters and, as you would expect, between the ship Minds.
After the rather serious and grim tone of more recent Culture books - fine though most of them have been - and great as it is to see Banks' writing at his funniest, it's the intelligence of the ideas underpinning the work and the deeper questions that they raise that make this science-fiction writing of the highest order. Since Look to Windward, the author has spent a great deal of time exploring these concepts relating to the non-material world beyond the Culture universe and offered tantalising glimpses of another reality, and he takes that another step further here in The Hydrogen Sonata, leaving just enough in reserve for further expansion. I'm not sure how long he can continue to draw this theme out, and indeed the latest book is somewhat repetitive of a formula established in all his recent SF books, but the richness and intelligence of the Culture concept still seems to inspire the author's best writing and The Hydrogen Sonata is the most entertaining work we've had from Mr Banks in a long time.