Those who have been paying attention to the evolution of Iain M. Banks' Culture series over the past two decades may have noticed that they are getting darker. His previous entry in the series, the fantastically disturbing and bleak Surface Detail, was about civilizations that consigned their inhabitants to a virtual hell after they died. Banks' latest offering, The Hydrogen Sonata, is also preoccupied with life after death, though it's slightly less horrific.
Actually, it is just as bleak — but in The Hydrogen Sonata, we are able to view the horror and misery of civilization from the amused perspectives of the Ship Minds who control the Culture. When you're super-powerful and super-intelligent, it's easy to find the frailties of biological creatures entertaining. In this novel, we follow a group of Minds who have tasked themselves with investigating the strange events surrounding the Gzilt civilization. Like a few other advanced civilizations, the Gzilt have decided to "sublime," converting nearly every member of their gigantic society into an entity that exists in another dimension that is something like heaven. Basically, they'll go through a classic Singularity scenario, where everybody will leave their bodies behind and exist in a dimension of total knowledge and abundance.
Unfortunately, only one Mind has ever returned from the Sublime to describe what it's like there — and it's a completely dotty entity who spends most its time collecting virtual dustballs and animals in a chunk of unused memory allocated to it by another friendly Mind. So the Gzilt have nothing but rumors to go on when they prepare to sublime. Still, the rumors are pretty great. A lot of other civilizations and Minds have done it and seem — based on their cryptic communications — to be enjoying themselves immensely.
The problem is that the Gzilt can't enter the Sublime successfully unless most people in the civilization do it at the same time. So it becomes an incredibly difficult political issue. Will everybody vote to end their lives and go to this place that's supposedly really great, at least according to unreliable sources? It's in this precarious political climate that something very strange happens. A ship left behind by another civilization that sublimed arrives in Gzilt space bearing a message — and is instantly vaporized. That's when the Culture Ships get interested. The Culture has always been an ally of the Gzilt, and they're helping out with the transition to the Sublime anyway. So they might as well investigate this juicy bit of unexpected violence.
In the process of solving the mystery of the message, we are treated to a scene of post-human politics that isn't entirely unfamiliar. "Scavenger" civilizations vie to become privileged partners in the Gzilt subliming, thus gaining access to all the technology and resources the rich Gzilt leave behind when they fold into another dimension. A thoroughly nasty Gzilt politician schemes to rule his world for the few weeks left before "ruling" and "worlds" become completely meaningless categories. Gzilt people, anticipating the end of days, have outrageous, multi-year parties that involve extreme body modification (you'll see). And a human who has lived for thousands of years may be the only person alive who knows what the message was on that destroyed ship.
Joined by a Gzilt musician with four arms (she's grown an extra pair to play the notoriously difficult and ugly Hydrogen Sonata), the Ships careen across the galaxy in search of answers . . . and all the while, the Gzilt get closer to their dubious heaven. Unlike the dark, disturbing Surface Detail, which is clearly a companion volume to this one, the tone of Hydrogen Sonata is melancholy and wry. There's a kind of deep sadness here — a familiarity with human failings that brings out Banks' best sardonic humor. Still, by the time you reach the final notes of the novel, you'll feel like the tone of this long-running series has gone from a kind of crazed, bloody hope for the future, to a resigned pessimism about it.
That's not to say the novel isn't a ripping good yarn. Banks never fails to tell a good story. In Hydrogen Sonata, he may have created one of most bittersweet, melancholy space operas you'll ever read.