Creation Lake by Rachel Kushner review – a thrilling novel of ideas

Bruno Lacombe, in his youth an ally of the 1960s revolutionary intellectual Guy Debord, is now self-exiled to a cave complex in the limestone regions of southern France. The caves are like a kind of political rhetoric in themselves, a message convoluted and endless. Their vanished inhabitants obsess him. Since the Neanderthal extinction, “the wedge between human beings and nature” has become “far deeper than the wedge between factory owners and factory workers that created the conditions of twentieth century life”. The left, he believes, needs to properly understand this.

Meanwhile, shadowy French authorities have decided that Lacombe and the “Moulinards” – the post-Debordian eco-commune he mentors by email – need to be steered out of their less than utopian rural domesticity and towards some act of serious terrorism, so they can be dealt with. So they hire Sadie Smith, a freelance American spy-cop, to infiltrate and provoke an outrage. The situation Sadie finds on the ground is confused and intersectional, centred on a real-life green issue: the diversion of local water supplies into vast “mega-basins” to support corporate agribusiness projects at the expense of the local farmers and the environment. Actors within and without the Moulinard commune, less in bad or good faith than in something shifting constantly between the two, all have their motives for protest or intervention.

At the outset, though she narrates Rachel Kushner’s Booker-longlisted new novel, we know very little about Sadie. She is 34 years old. Her self image is one of self-confidence and control. She is good at what she does, and contemptuous of her victims. Her assessments of them are cruel. A fixed self underlies every individual’s ideological relations with the world, she seems to have decided, whatever they have taught themselves to believe; and it’s this confusion that makes them so easy to manipulate.

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Bruno, meanwhile, announces to his followers that Neanderthals still live, and may even walk among us. He’s heard “human talk” in the caves: “Sometimes it’s in French, sometimes Occitan, or older tongues of the Languedoc, many languages I do not recognise … ” These communications, Sadie concludes, are neither historically nor palaeontologically sound, but represent a self-indulgent retreat from his own life, a transition from politics into metaphysics. As Debord retreated from the failure of the 1968 left into a kind of agrarianist alcoholism, so Lacombe has bought into medieval conspiracy theory, one of the Languedoc’s leading exports.

Sadie isn’t sure what to make of this, but Lacombe’s curiously one-sided email contact with the Moulinards stimulates in her an unspoken conversation with him; and though the provocateur and the old activist never meet, their dialectic supplies the backbone of the book. Staring up at the vast limestone overhangs as she dips her hand in the ice-cold water of a local spring, Sadie feels the presence of the ghosts in the stone. Later, as things fly apart, and provocation turns into black comedy, to the subsequent confusion of all parties, she begins to feel she has learned something from him; something new about herself.

Throughout Creation Lake we catch tones of voice that remind us of Kushner’s essays. “I like poplars,” Sadie tells us. “A straight line of them makes me think of driving, of going fast, into low Western sun, its rays illuminating their rippling leaves … They are trees that remind me of a time I felt invincible.” We are immediately bathed in the harshly lyrical moment of The Girl on the Motorcycle or We Are Orphans Here. A moment later, we’re learning everything we might want to know and more about the domestic organisation of a contemporary left-green commune, or the history of the medieval Cagot communities of western France – leading to the suspicion that Sadie might be less a spy than a longform journalist, or that spies and longform journalists might share some of the same qualities.

If shifts of register like this help construct a lively, timely, satisfyingly rough-grained novel of ideas, they also make for an excitingly complex and fascinating narrator. In the end, it’s hard not to see Sadie herself as the subject of the author’s gaze; the conundrum that maintains Creation Lake’s narrative drive. She believes in the “truth” of the individual, “a substance that is pure and stubborn and consistent”. Yet, professional considerations aside, she maintains her life as a tension between purism and laissez-faire. She likes wine, she might even be said to be a connoisseur, but she doesn’t care what she drinks. She likes, or has liked, to drive, but she is no longer a petrol head. She likes older, unreconstructed men but is as given to patronise them as she is men of her own age, whose experience is only ever of cultural product, “some banal pop song, a romantic comedy, an August vacation”, and who, unlike their grandfathers, or even their Boomer fathers, have never undergone “encounters with war and killing and death … a true and real loss of innocence”.

Sadie is a triumph of character – not quite fully self-deceived, not even entirely corrupted by the barely controlled confusions, emotional complications and near-disasters of the deep-cover agent’s life. She’s a satire, but she’s also being straight with us. She’s not quite a sensationist, although the world pours in on her senses, and through hers into ours. How, Kushner asks, does the individual’s embrace of experience interface with the ideological? In what circumstances can ideology even permit an interface? Sadie Smith is perhaps both question and answer.

• Creation Lake by Rachel Kushner is published by Jonathan Cape (£18.99). To support the Guardian and the Observer buy a copy at guardianbookshop.com. Delivery charges may apply.