Radical politics, mixed-up heroines and the threat of violence are staple ingredients in the fiction of Rachel Kushner, who began to be spoken of as one of the century’s great American novelists with her second book, The Flamethrowers (2013), about a biker in the art world of 70s New York and Italy during the “years of lead”. But even though her third novel, The Mars Room, set among women serving life in a California prison, was shortlisted for the Booker prize in 2018, I’m not convinced she’s truly on the radar of most readers this side of the Atlantic, where we’re warier of the vast, chiselled, ideas-packed tales ambitious American writers are less likely to shy away from.

Her hugely enjoyable new novel, Creation Lake, already longlisted for this year’s Booker, ought to put her firmly on the map. An espionage drama pulsating with twisty revelation and drip-fed backstory, dealing with anarchy, agriculture and prehistory, it adds a killer plot and expert pacing to the reach and sophistication of her previous work, as well as vital fun. The American narrator, 34-year-old Sadie, is another memorable Kushner heroine, a polyglot ex-postgrad blessed (she tells us) with a knockout figure and plain face – all the more handy for her role as a spy for hire in the wake of being booted out by the FBI after a bungled bid to entrap an animal rights activist.

We join her in Guyenne, south-west France, where she’s now being paid to track the founders of a radical farming co-op, Le Moulin, suspected of disrupting a government-approved scheme to turn local fields into a corn-based monoculture. A shadowy paymaster, never named, has tasked Sadie with finding evidence of their foul play – and if she can’t, to generate it herself by whatever means available.

The opening pages cut between Sadie’s journey to Guyenne and her illicit reading of hacked correspondence between the Moulinards and their elderly guru, Bruno, a cave-dwelling former soixante-huitard who regularly surfaces to tap out emails on his daughter’s computer, unspooling eccentric theories about the fate of the Neanderthals – for him, a much-misunderstood species from whom we can learn a lot, not least their recognition (apparently) of the subversive potential of sleep.

As Sadie beds into the commune, disguised as a translator, much of the early intrigue lies in how Bruno’s thoughts – an out-there mishmash of speculation and fact pertaining to the real-life persecution of the local Cagot people – are not just silly but seductive, even as they are sieved through Sadie’s wry summary. The drama deepens when she gets closer to Le Moulin’s leader, Pascal, a wealthy Parisian ex-confrère of Guy Debord, as the novel starts distributing our attention among an impressively wide range of settlers. We see how the commune’s dangerously lax norms permit murky goings-on – an 11-year-old father gets a key role in the story – and the constant needle among its diverse population of rural folk and young intellectuals down from the capital, as well as factory workers licking their wounds after failed strike action. There’s also a serial felon from New York, previously seen in The Flamethrowers, whom Sadie’s keen to arm when things hot up; and there’s even a thinly disguised cameo for Michel Houellebecq, or “Michel Thomas”, perfectly captured as he rocks up at the action’s peak to research an “agronomy novel” (2019’s Serotonin, the closest Kushner comes to giving her novel any kind of time stamp).

The biggest drama, though, is Sadie herself. From the off, there are hints that – surprise – spies don’t tell the full story. An early reference to “a valley of pure green, like you’re gazing at the landscape through a Heineken bottle” isn’t flim-flam but a sign that our narrator might be doing just that. She claims she’s better able to handle her rental Skoda hatchback with help from a few drinks en route, but as the narrative reaches boiling point, she’s missing her alarm call in a Xanax and whisky fug.

It’s fairly unusual these days for a novel to throw the kitchen sink at luring you into the worldview of a bona fide villain serving powerful interests, but that’s what we get here. (Not that the farming co-op represents any kind of idyll – Creation Lake is the sort of novel that puts a plague on everyone’s house.) Sadie’s CV includes hawking fake Picassos on behalf of a dealer out to discredit his rivals, and yet we can’t help rooting for her; it’s a particular thrill, at one point, to see her muzzle a suspicious local by wielding a tasty bit of kompromat. For stretches of the story, she’s basically an all-conquering superhero. But then there are the flaws in her armour – the vulnerability deduced between the lines – as when she vaunts her reflexes and sensitivity to danger during a comfort break pitstop in the bushes (her bladder full of motorway service station wine, as she doesn’t quite spell out), before contriving to pee over herself because she’s spooked by footsteps that turn out to be nothing but her own, crunching a crinkly food wrapper.

To Kushner’s credit, the novel doesn’t try to daub Sadie’s actions in shades of grey, even as it flirts with the notion that nothing less than full-on addiction allows her to maintain the self-deception necessary for elite-level deceit. This novel is bolder than that. It isn’t any sense of the narrator’s buried pain that keeps us riveted; it’s more that, for the reader, she’s excellent company on the page – boastful, vituperative, wild, telling us about her breasts, her contempt for Italian food, why graffiti is more heinous than murder, and what “the real Europe” is: not “a posh cafe on the rue de Rivoli with gilded frescoes and little pots of famous hot chocolate”, but “a borderless network of supply and transport … shrink-wrapped palettes of superpasteurised milk or powdered Nesquik or semiconductors … highways and nuclear power plants … windowless distribution warehouses”.

For a long time, the closest the story comes to the pulling of a trigger is a sick cow callously put out of its misery at the halfway point – a bullet fired just to remind us that what Chekhov said about a gun on stage must apply to the four that Kushner’s anti-heroine has stashed up her sleeve. The final 100 pages, pinballing between peril and farce, are amazingly tense: wall-to-wall entertainment, and a real treat.

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