Jerusalem, By Gonçalo Tavares Dalkey

Mylia, Theodor, Ernst and Hinnerck Obst. It is 29 May, late at night, and each of these characters is out on the streets, adrift. Mylia seeks pain relief, food and a church. Theodor has abandoned his son at home and is on the hunt for a prostitute. Ernst has decided not to jump out of his window and has come out to rescue Mylia instead. Hinnerck Obst, deep bags under his eyes, is carrying a gun.

Also out on the streets is Kaas, raised as Theodor's son but really child to Mylia and Ernst (conceived at the Georg Rosenberg Asylum, where they were inmates). And out there tonight young Kaas meets the man with the gun. Gonçalo Tavares lures his characters through their stories, now tracking back to show us how they came to be here, now returning to this night when they and their troubles and that gun have all come hurtling together. Violence, tonight, is inevitable.

Theodor is a doctor whose grim area of special study is cruelty on a massive scale – concentration camps, massacres of innocents, genocide; he is producing a vast historical assessment of these events, and by surveying how the numbers add up over time (is evil increasing or decreasing?), he means to predict either the end of such atrocities, or the ultimate mega-atrocity that will eliminate everything in some terrible cataclysm – or to conclude that the pattern is regular and cyclical and our species is doomed to repeat the cycle of horrors for all eternity. (He intends to produce a handy formula. He is a scientist, after all, and as such believes that things always ought to add up sensibly.)

Over the course of the night Tavares' characters come together, sometimes helping one another towards redemption, sometimes nudging one another towards catastrophe. The latter is more common than the former, for Tavares is not a novelist who doles out easy redemption readily. Rather, his subject is the chaos of human interactions, the sorts of damage people can inflict on one another in a society where choices we make to benefit ourselves have costs others must bear.

Like Theodor, Tavares is interested in the nature of evil and cruelty, and the limits of sanity, and the world he creates for his characters is unremittingly hostile. Brief glimpses of something that might look like hope – two inmates in an asylum find something approaching love – end badly. Tavares anatomises human weakness and impulses, and with his decidedly chilly prose pins down a city of loneliness, violence, madness, immorality, isolation and pain. He questions the links between madness and immorality; extreme behaviour and the search for normality; the impulses of those who perpetrate violence and its victims; struggles to survive and the lure of dying, or killing. And this is also a book about power, and about characters with no control over their own lives. Characters in Tavares' world are kept permanently unsettled. The feeling rubs off on to his readers.

The compartmentalising of characters means that in one sense Jerusalem's story is fragmentary – there is no single line of consecutive plot, but various strands to be woven together, the chronology interrupted and complex; but it never feels as though it lacks a centre, and out of these unhappy fragments, Tavares has created something compelling, darkly beautiful and driven, and totally original. Jerusalem is not an easy book to read – at least insofar as it is more disturbing than reassuring, its characters are damaged and their stories distressing, the whole stripped back and entirely unsentimental. Yes, it's bleak – but it's also daring, thought-provoking and brilliant.