Before even its title page, Baron Wenckheim’s Homecoming comes prefaced with a “warning”. Over the course of seven pages, which may or may not have anything to do with the 550 pages that follow, an orchestral conductor delivers a peroration that is also a rant that is also a kind of philosophical projectile missile. Though it seems to be addressed to his musical performers, it’s unclear whether this isn’t actually one long interior monologue, bringing to mind the troubled babble of Samuel Beckett’s Not I.

This conductor is obsessive. About his violinists he declares: “I want to know even their most idiotic thoughts concerning the falling resin dust, or how often they trim their nails.” A glass-completely-empty type, he tells his musicians: “Apart from your admittedly modest compensation there is no reward whatsoever, of course, accordingly, no joy, no consolation.” And he is happy being thought of as a dictator: “There is no point trying to oppose me, no sense at all.”

Baron Wenckheim’s Homecoming may not bring joy or consolation, but reading it is a mesmerisingly strange experience: a slab of late modernist grindcore and a fiercely committed exercise in blacker-than-black absurdity. Hungarian-born László Krasznahorkai, winner of the 2015 Man Booker international prize and best known for Satantango (1985), later made into a legendarily dour seven-hour film of the same name by Béla Tarr, has described it in summative terms: “I’ve said it a thousand times that I always wanted to write just one book … with Baron, I can close this story.”

Its “story”, if indeed it can be called that, involves the sexagenarian Baron Wenckheim returning in the present day, after a gap of more than 40 years, to the Hungarian town where he was born, during which time he has racked up huge gambling debts in Buenos Aires. His memory is rather hazy, and his wealth non-existent. The locals, who don’t know this and plan to fleece or profit from him, act as if he’s a hero and saviour. The only exception is Marika, the Baron’s childhood sweetheart, who harbours thoughts of being reunited with him.

Meanwhile, a Professor – “one of the three most important moss experts in the entire world”, according to Nature magazine – is holed up in a ratty hut on the edge of town. He’s lost interest in mosses and is deeply annoyed at being confronted by his 19-year-old daughter who shows up, accompanied by a TV crew, trying to get the maintenance payments she’s owed. Soon, inasmuch as anything happens quickly or sequentially in this novel, he’s forced to go on the run after shooting a member of a biker gang.

Long stretches of the novel lie there, slow and exhausting, like call waiting, drone music, middle age

These journeys and descents have a morose density that’s made all the more potent by the book’s syntax. Krasznahorkai’s sentences go on for pages and pages. They are held together – shades of Tristam Shandy, here – by dashes and ellipses rather than full stops. They are laden with clauses within clauses, full of conditionals studded with conditionals and explanations that also contain explanations, indifferent in punctuation terms to whether a character is speaking or just thinking. Long stretches of the novel lie there, slow and exhausting, like call waiting, drone music, middle age.

This is a high-wire act on the part of the author, and a gamble – or act of faith – on the part of the reader. It’s also an experiment in suspense that recalls the shaggy-dog detours of improvisational comedy. Krasznahorkai, though he’s often presumed to be a miserabilist, Mitteleuropan chiliast, is a very funny writer. He unfurls dense, seemingly endless sentences that are suddenly punctuated with unlikely phrases such as “Hungarocell panel” or “scribbling riffraff” (rendered into English by translator Ottilie Mulzet). He comes up with odd similes – a woman leans forward “like Nike of Samothrace” – and includes knowing gags to illustrate how terrible a particular day is (infanticide, epidemic, a new exhibition by the German artist Gregor Schneider). There are surprisingly contemporary allusions to iPhone photo galleries and the Brazilian footballer Dante.

Much of the humour is directed at the burghers of the provincial town where the Baron and the Professor have landed up. Most of them are reduced to the social functions they so pompously perform: the Mayor, who makes an inept choir sing a mangled version of “Don’t Cry for Me Argentina” for the Baron; the Director of the local library, who patronisingly chides an employee for using “Germanisms” rather than “correct Hungarian”. An early inkling that the Baron’s return trip will end in failure comes when he talks romantically about Hungary as his “ancient homeland, a land of fables”; later, walking around the glum streets of his youth, he wants to cry. “This was not the same town, and yet he was compelled to acknowledge that it was exactly the same, but it was as if somehow it had become a copy.”

Immigrants represent the novel’s background noise. They are everywhere – or at least they seem to be. On trains, begging on streets, getting into fights. Gypsies, Albanian gangs, mangy outsiders, polluters of pure Hungary: described in the language of flotsam and filth, they lurk at the edge of the text, cast out from their pasts but unable to get a purchase on a stable future, as displaced and dislocated in their fashion as the more central characters.

Krasznahorkai implies that such dislocation – destruction, even – is what Hungary needs. The Baron and the Professor recede from view leaving in their wake a town ripe for revelations. The fascists get heavier, the mood darker. The Chief Editor of the local newspaper convenes some of the town’s dignitaries in order to read aloud an anonymous jeremiad he has received. “To be Hungarian is not to belong to a people, but instead it’s an illness, an incurable, frightening disease, a misfortune of epidemic proportions that could overcome every single observer with nausea.” DH Lawrence railing against England or Thomas Bernhard raining down curses on Austria seem mild-mannered in comparison. “Hey, you, putrid Hungarian,” inveighs the letter writer, “you’re spineless and two-faced, perfidious and contemptible, lying and rootless, because after you’ve exploited somebody, you do the same thing, namely you throw them away, you spit into their eyes, if they’re not good for anything else, because you’re primitive, you worthless Hungarian …”

Make no mistake, Baron Wenckheim’s Homecoming is gloomy, frequently inert, boring, frustrating. Its more vatic passages can feel superfluous (“The world is nothing more than an event, lunacy, a lunacy of billions and billions of events, and nothing is fixed, nothing is confined, nothing graspable, everything slips away if we want to clutch on to it”). Yet it has a madness and monomania that compel. Exhilaratingly out of step with most contemporary fiction, it’s closer in spirit to Gertrude Stein’s The Making of Americans, a novel whose syntactic difficulty creates a literary no man’s land for intrepid readers to yomp through. Not even 600 pages, it’s both too long and – in this era of rolling news and data dumps – far too short.

• Baron Wenckheim’s Homecoming, translated by Ottilie Mulzet, is published by Tuskar Rock (RRP £20). To order a copy go to guardianbookshop.com. Free UK p&p over £15.