Northern Ireland came to the fore last year with outstanding books by Anna Burns, Wendy Erskine and Michael Hughes. Now David Keenan, author of 2017’s accomplished and original debut This Is Memorial Device, and a Scot with Irish roots, enters the territory with a novel set in the Ardoyne area of Belfast in the 1970s and centred on members of the Provisional IRA.

The loquacious narrator, Samuel McMahon, tells his story, apparently to an investigative reporter “or some other do-gooder”, while incarcerated in the Maze prison. His self-described “happy days” make up much of the novel: a frenzy of beatings, shootings, extortion and robberies with his friends and fellow Provos Tommy and Barney.

Keenan focuses on the generation of republican paramilitaries between the “corrupt” old guard, as a character describes them, and the highly politicised cohort that followed. Sammy and his friends are largely uninterested in politics. They are devoted to their pals, their locality, their tribe, and to having a good time. They are glamorous in their own minds, and to many of those around them: representatives of an extreme, volatile and brittle masculinity, acting out in the war zone created by partition. Much of the novel is related in a drily comic register that will challenge the reader who wonders just what’s so funny about all this.

Keenan writes the violence of the paramilitaries with vividness and immediacy, or, to put it another way, with no excuses. He captures a permanent brutal present, experienced sometimes orgiastically by its perpetrators, with the targets being the security forces, the wrong kind of neighbours, “traitors” and strangers. Violence saturates and distorts their relationships with one another, and particularly with women. Kathy, held by Sammy and his associates to force her husband to pay overdue extortion money, tries to get them to see how their actions appear: “Is this what it’ll be like in a united Ireland, she says to him, and the tears streaming down her face. Kidnap, torture, rape, she’s saying, is this what the future adds up to?”

In a world of inherited lines of conflict, neutral narration is only possible when born out of ignorance or pretence. By telling the story with the voice of Sammy – killer, loyal friend, indifferent revolutionary – and by holding the reader close to the pleasure he feels in his choices, Keenan is either giving the reader a rare chance to reflect on the intoxication with violence at the heart of our culture, or providing us with a florid example of its celebration. A switch of viewpoint halfway through the book, from Sammy to an artist who is immolated in the British embassy in Dublin during the protests after Bloody Sunday, plunges us into a world of violence as unending nightmare. This might provide an answer to that question, but I could not in the end be sure.

Part of his approach, which takes him a long way from the Troubles as they usually appear in fiction, is often to enter into the unreal in a hallucinogenic mode that encompasses comics, the occult and drugs. The book nods to Aleister Crowley, and Keenan repeats occult snake and heart imagery throughout, as a symbol of violence in Irish history and its eternal return – the British and their interests being oddly missing from this figure.

In another narrative thread, the central characters take over a comics shop, as a punishment for the owner’s failure to pay protection money. They run it first as a source of income for the IRA but soon become obsessed with cosmic tales of superheroes. One character reimagines the Provos with their own strange powers in an interleaving episodic narrative that acts as an esoteric counterpart to the main story.

There is an implication here that the millions of words that have been written elsewhere about the Troubles have failed to capture the texture and interiority of this history; the horror, the hauntings of act and place, the failures of individual agency in a world of overdetermining fate. This is a style that is at times innovative and energised and at others can seem self-indulgent, misdirecting the reader from the non-esoteric realities of war and power.

For the Good Times is a powerful novel, but what is uncertain is the nature of that power. The narrator’s dodge into forgetfulness at the end of the book would not convince any of the living participants of the Troubles. There is no attempt to understand, in the words of Louis MacNeice, born a mile and a world away from Sammy, that we “have to gesture, / Take part in, or renounce, each imposture” within all of Ireland’s inheritances. But perhaps the heart of the book, and its real conclusion, lies in Sammy’s earlier words: “What if the truth is a stinking pit filled with bodies? What if the truth is the blind pain at the centre of the world? ... Maybe it would be better for us all if we just played the game.”

• David Hayden’s Darker With the Lights On is published by Little Island. For the Good Times by David Keenan is published by Faber (£12.99). To order a copy go to guardianbookshop.com. Free UK p&p on all online orders over £15.