Professor Andersen's Night, By Dag Solstad, trans. Agnes Scott Langeland

It is Christmas Day, and the Halvorsens are having a dinner party, long-planned with "elegant" seating arrangements. Their guests are, like themselves, successful professionals, friends since radical youth but now, lauded and into their fifties, arbiters of Oslo society with opinions that count. They skål one another with beer and aquavit over their raskfisk, which they follow with grouse washed down by Rioja.

Conversation is easy with much cheerful laughter. But for one guest, Professor Andersen, the occasion is more oppressive than enjoyable; he struggles "with a disturbing feeling that he had now parted from [his friends] for good". This is not because of his growing doubts about his own position and achievement (he is a distinguished Ibsen scholar), though these plague him with a feeling that he is living in an "end-time". Nor is it on account of his status as a childless, partner-less divorcé among married folk who exchange family anecdotes. No, the reason is that he alone witnessed a murder on Holy Night, that transition between Christmas Eve and Christmas Day which tradition cites as the time of Christ's birth.

During this solemn hour, Professor Andersen dealt with his loneliness by looking out of his apartment's main window at the block of flats opposite, to catch glimpses of other people's lives. He saw a young woman appear at the lighted window of one of the smaller apartments - slim, fair-haired, young, beautiful. He saw her turn round as a young man came into the room. He saw this same young man put his hands around her neck, and squeeze it until her struggling body expired.

Never throughout this exquisitely composed novel do we doubt that all this met Andersen's bemused eyes. "'I must call the police,' he thought. He went over to the telephone but did not lift the receiver. 'It was murder. I must call the police,' he thought, but still did not lift the receiver. Instead he went back to the window."

This consuming inertia does not leave him. Admittedly he turns up eccentrically early to the Christmas dinner party expressly to tell his old friend Bengt Halvorsen what he's seen. But "he couldn't bring himself to talk about it". Weeks pass, and there's no news of any young woman's corpse being discovered. So has this astonishing event – death of unknown female rather than birth of male saviour – removed articulacy from one renowned for it? Andersen soon knows the name of the young man whose apartment the crime scene was, and what he looks like. Then, by happenstance, he encounters him in a downtown sushi bar, a mesmerically realised scene.

Despite murder's centrality and the vivid Oslo setting, this novel is no piece of Nordic noir. Its progenitors are French existentialism, the nouveau roman with its subtle play of time on space, and Austria's Thomas Bernhard with its long sentences following the contortions of a mind defying rational intentions. Dag Solstad is an unflinching explorer of the plight of educated humankind in the face of the inexplicable, whose artistry matches his ambitious theme.