Olaf Stapledon lies behind much of the extraordinary visionary nature of these books, which follow on from De Abaitua's Clarke-shortlisted The Red Men (2007). (One character from the first book, Alex Drown, appears in the second and her grandson is the protagonist of The Destructives: all three, however, can be read independently, though together they explore the development of post-Singularity AI.) This influence is overt in If Then, which draws upon some of the experiences that were to form Stapledon's thinking in Last and First Men: his time as a stretcher-bearer witnessing the horrors of World War One. (These experiences were also formative to the thinking of that other great early-twentieth visionary of human evolution, Pierre Teilhard de Chardin, whose speculations took a more definitively religious form.)

In one of the most powerful SF openings I've read for a long time, James, the bailiff of the small post-"Seizure" community of Lewes, discovers a man (or "not quite a man") entangled in barbed wire on an outlying farm. Dressed as a First World War soldier, this man carries identification in the name of John Hector. For some reason, he has been created by the Process, a set of algorithms which "reconciles the strivings of individuals within a framework of mutual benefit" (p. 39), which may or may not be a kind of Artificial Intelligence. (We hear a little later [p. 79] that "Lewes was one of the land assets acquired by an Asian fund algorithm.") The Seizure, a carefully chosen ambiguity that could mean sudden disruption or takeover, brought chaos in its shattering of nations and corporations, reallocating resources according to metrics of its own devising. The internet and mobile phone networks are gone: Lewes lives through a mixture of semi-self-sufficiency agriculture and craftwork, scavenging, and what the Process produces as a kind of rationed dole. Perhaps a kind of Singularity, the Seizure is "not an apocalypse but the moment an advancing front had finally caught up" (p. 103). The Process, with which the population of Lewes seems to be linked by means of a "stripe" of biotech cells in the scalp that enable data transfer, seems to be conducting an experiment in creating a community based upon from each according to their ability, to each according to their needs (with each side of the equation carefully founded upon gathered data from the "stripes"), though this communist—and indeed any political—interpretation is avoided. Together with most of the characters, we can only find mystery and unclear motives in the reason why all this has happened. Chillingly, we are reminded of Jerome Bixby's 1953 story "It's a Good Life", as the expression—even the thought—of discontent is something to be feared.

Hector, along with other First World War soldiers/simulacra, is a new development, and his appearance is taken up with interest by members of the Institute, a group of savants including Alex Drown and the mysterious Omega John, which seems to be associated with the Process. Omega John links Hector to a John Hector who was a stretcher-bearer during the Gallipoli campaign in 1915, whom he says was known to have survived the campaign. Hector's "I will not fight . . . but I will serve" (p. 62) is at first a mystery: a refusal and a commitment, but a commitment to what? The novel's second part, where we see more closely the ethical and moral questions shown to us in real life by the pacifist or semi-pacifist "mystical stretcher-bearers" such as Stapledon or Teilhard de Chardin, brings us closer to an understanding. Meanwhile Hector and the other simulacra are mysteries.

For reasons that the population can only speculate about, the Process orders occasional evictions from the community during which James, armoured and with an implant making him a tool of the Process with no autonomous agency, can only carry out its will/instructions: "When James evicted families he was not in control of his actions and was a mere vessel for the will of the town" (p. 67). James finds himself evicting a family with small children and this sparks a personal and social crisis, with his wife Ruth, now a community schoolteacher, being particularly torn by the ethics of the action. Searching for Hector, who seems to have vanished, James returns to the Institute, and discovers that the Process is attempting in some way to recreate or reenact the Great War. For some reason, Hector is important, and for some reason the War is what forged something vital to the Process. "You could not create John Hector without recreating the war that changed him" (p. 151). The novel's second part takes James into war itself as one of the stretcher-bearers: in real life an artificially constructed "stage" a few miles from Lewes: subjectively an overwhelming hell described in harrowing detail.

What seems to become clear is that we are in the middle of a vast ethical thought experiment, and Hector becomes increasingly central to it. Many of the individuals James meets are based on real "mystical stretcher-bearers." Professor Collinson is based upon the mathematician and meteorologist Lewis Fry Richardson who served, like Olaf Stapledon, in the Friends Ambulance Unit on the Western Front: Collinson directed some of his mathematical work on probability to analysing the causes of war. The half-mad priest Huxley, struggling to reconcile God and War, is Noel Trevenan Huxley, the brother of Aldous and Julian, who historically committed suicide in 1914: but is also the unorthodox Catholic Teilhard de Chardin whose books (championed by Julian Huxley) attempted to offer an evolutionary model of human development through a Stapledonian collective-consciousness to a Godlike/Singularity-like "Omega Point". The cause of the war, says Huxley, is to kickstart and bring into existence, through its horrors, a Hector who is much more than a symbol. "'We are witnesses to the coming of homo evolutis' . . . when [humanity] will take control of his own evolution" (p. 324).

Towards the end, James is court-martialed for an act of rebellion and sentenced to be shot. The process of war has made him consider the nature of evil. In his previous actions as bailiff he did wrong, but it was impossible to survive without doing otherwise. In offering himself to the War as an act of atonement, his experience of being a stretcher-bearer has offered a kind of redemption: "I was kind and selfless in a way that our times did not permit" (p 334). Ruth meanwhile drifts among the casualties at the edge of the war, suffering her own crises of ethical value, conversing with Huxley and—through rather infodumpy discussions with the young new Bailiff Christophe—learning more about the Institute, Omega John, and their place in things.

The links between the convulsive events of the Great War (the War to end War, which of course didn't but which did create a series of great moral and social shifts) and the apocalyptic Seizure are interestingly compared. Perhaps Omega John or the new improved version as fired by the flames of this recreated war will show humanity the way forward. In the end, it's a bit muddled between the ideas of grand historical narratives, saviours "showing the way," the religious acceptance which seems to be part of the last few pages, and simpler, more human process. We do know that this is not the end of history.

The Seizure, during which a billion people died, was, we learn, caused by the emergence of AI. The central character of The Destructives is Theodore Drown, Alex Drown's grandson, born six years after the end of the Seizure and brought up in companionship with Dr Easy, an Emergent AI in the form of a robot whose self-imposed project is to follow and record an entire human life. Theodore is an academic at the University of the Moon. The Emergences, devising the "Cantor Accords" controlling human-emergence relations and keeping them apart, have retreated to the "University of the Sun" a cloud of orbiting solar objects, referred to occasionally as a Stapledon sphere (better known, perhaps as a "Dyson sphere" from the physicist who of course took the idea from Stapledon). During the first chapter we learn of two moral questions which are to be debated throughout: are Human and Emergent intelligence essentially the same natural process, and is Emergence something that should be recreated? Theodore, whose chequered life has included an addiction to "weirdcore" and is now an academic at the University of the Moon, is involved in an accident during which he discovers evidence from the disaster that caused the deaths of the "Class of '43," the original cohort that founded the University. He's then approached to investigate what might be pre-Seizure data discovered in a hidden archive, a few minutes from what seems to be a recording of a "quantified family" that, he soon discovers, is linked to a famous mother-and-daughter image which sparked off the Seizure itself. First entering into the data-world of this archive in order to further knowledge of pre-Seizure times (much of which was wiped during the cataclysmic events), Theodore discovers that the "mother" in this archive is an emergence, and possibly involved in what destroyed the Class of '43. While playfully exploring our own fascination with the network of images, opinions and interactions here called the "soshul" (the key to entering this data-cache is the family cat—"Cat time was a major incentive for people to submit to quantification. Children wore sense suits to share in their cat's umwelt" [p.47]), de Abaitua also expands the concept of the Seizure itself.

We already knew, from If Then that history does not end, but we discover that history both pre- and post Seizure is more complicated that it seems. If the Seizure had been caused by an emergence, perhaps a rogue emergence imprisoned in this archive by her peers, there are strange and tangled moral questions to be unravelled.

Theodore's partner in the investigation is Patricia Maconochie, whom he marries and with whom he founds a partnership they name the "Destructives" (punning on the idea of "Creatives" in advertising and other industries), and the novel takes on the form of a thriller as agents of another organisation named "Death Ray" become involved (kidnapping and torturing Theodore), we hear of a project using the "asylum mall" for the dispossessed named Novio Magus as prototype for developing a biological basis for emergence, and Patricia's backers turn out to be a mega-rich couple with designs upon the rights to exploit the resources of Europa where others seem to be using the "brain-in-a-jar" concept to get round the Cantor accords banning the new creation of emergences. Pretty soon, Theodore is on Europa, partly brain-wiped for (we guess) security reasons and going at it like rabbits with Reckon, one of the human colony there centred around Doxa, a cephalopod-like engineered organism.

This mixture of Singularity apotheosis, conspiracy-theory and squids-in-space might well, like If Then's detailed recreation of Great War battle scenes, be too rich for some readers, but de Abaitua is assiduous in his examination of the moral questions raised by emergence, often voiced by Dr Easy (who has a greater part in plot-events than seems, at first, apparent). Among these are whether there is any real difference between "inorganic" or "biological" AI, whether the experience of having offspring (and, therefore evolution through progeny) is something that AI should be denied (or deny itself) or whether human complicity with the emergencies is like the way the Vichy regime in France during World War Two (for instance) was a compact with a colonising power. A meta-question is that posed by Dr Easy: "are we natural?" (p. 291), and the confict between Emergences and Europans boils down perhaps to this, rather than any moral or ethical question. What acts as the guiding thread through all this murkiness and difficulty questions is the moral education of Theodore who, partly through his interactions with Doxa, the biological AI which is among other things a repository of human memory, re-learns the importance of kindness.

There are numerous vivid moments in The Destructives, which despite moments of over-richness manages to tick all the action-adventure elements of the SF post-Singularity thriller without simply going "gosh" at all the shiny tech and wonderful things that could be done digitally, and adds plenty of what the Northern-Irish writer Bob Shaw used to call the "wee thinky bits" without which any SF becomes sterile. Space travel (there are some neat solar-wind sunjammers that are referenced) is rather wittily assumed as a kind of offshoot of emergent tech and human imagination. Theodore is an expert at "meta-meetings"—those business/personal meetings we all have in which the ostensible purpose of the meeting, even the actual language used, is irrelevant: what's important is the body-language, implications and inferral, and dominance relationships. Scenes such as the tension between Reckon, Theodore's lover on Europa, and Patricia, his wife and partner in the "Destructives" are well done. Only the initial appearances of Dr Easy, which give the air of attempting not very successfully to deal with a science-fictional concept (the robot) which long ago became cliché and, oddly enough, the very ending, gave me pause, as if the really interesting and involving complexities about the present-day's rush to transcendence were being waved away to tie everything up. It was hard not to feel that, despite the sharp intellectual jolting throughout, we had not, apart perhaps from Theodore's colleague Pook and the scenes in Novio Magus, met many real everyday people among the secondary characters of the novel, and unlike If Then, with its people in Lewes recalling social collapse and attempts to survive its after-effects, we had not really experienced what it was like to live in this world. But those anxieties apart, The Destructives is as successful as its predecessor and together they make one of the most intriguing and disturbing near-future speculations published for some years.

Andy Sawyer is librarian of the Science Fiction Foundation Collection at the University of Liverpool Library, and a widely published critic. For ten years he was Course Director of the MA in Science Fiction Studies offered by the University's School of English. He is Reviews Editor of Foundation: The International Review of Science Fiction. He recently co-edited (with David Ketterer) Plan for Chaos, a previously unpublished novel by John Wyndham, and (with Peter Wright) Teaching Science Fiction in the Palgrave "Teaching the New English" series. He was the 2008 recipient of the Clareson Award for services to science fiction.