You haven't seen an England quite like this-so grim, so dark, so brown, so Indian. Sunjeev Sahota's new novel The Year of the Runaways, longlisted for the Man Booker Prize, is not about the Englishman's England. Sahota takes you to the land of the "fauji"-the slang for the poor, illegal Indian who washes up on England's shores and streets to make a living. Somehow. Anyhow. They scour dishes in shabby restaurants, they step into sewage lines to clear giant blobs of fat, they work for less than a pound a day on construction sites. They fly with just a rucksack from Delhi to Ashgabat to Turkey to Paris and then hide in the back of a lorry that is ferried to England. Sahota takes you through a year, just a year, in their lives. Lives, which change with the seasons.

Of the 11 writers who made it to the Man Booker longlist, Anuradha Roy is the only Indian, with her intense, disturbing novel Sleeping on Jupiter. Sahota is a 34-year-old, Indian-origin British writer. Born in Derbyshire, trained as a mathematician, Sahota shot into prominence in 2011 with his first novel, Ours are the Streets, about a Pakistani immigrant who decides to become a jihadi. Sahota's literary consecration happened a couple of years later, in 2013, when Granta magazine named him as one of the 20 most promising British novelists. Incidentally, Salman Rushdie, the man who was on Granta's first such, much-celebrated list in 1983, has blurbed Sahota's new book: "All you can do is surrender happily, to its power."

It is winter in Sheffield when three young men, Tochi aka Tarlochan Kumar, Avtar Singh Nijjar and Randeep Sanghera, come under the roof of a stinking shared house. The year is 2002. Sahota does not labour the point, but you cannot escape the fact that it is the year of the Gujarat riots. In Sahota's Bihar, a white banner of the Hindutva organisation Maheshwar Sena shouts: "Bharat is for the land of the pure and blood we shall shed to keep it pure." Sahota does not allude to Gujarat at all, but he does not let you forget a pregnant girl whose belly is cut open by rioters.

The three youngsters carry the scars of their homeland, none more so than Tochi. He has fled his village that was consumed by the fire and hatred of caste riots. Tochi, who was abused as "chamar" and "scheduled" on Patna's roads, came to England to "choose his own life". But he can't escape the shame in Sheffield either. The place has changed, but not the people. Geography has not been able to right the wrongs of history. Sahota shows how the immigrants haul into the new country their dirty baggage of prejudice-regarding caste, religion and gender. It does not get sanitised at the immigration counter.

The three men are joined by Narinder Kaur. She is a young British-Indian woman, but she is more a traditional Indian than a modern Brit. She wears her turban and spends her time in gurdwara and becomes a "visa-wife" to young Randeep so that he could live and work in England. Sahota's narrative follows the path taken by these youngsters. It painstakingly details their every movement. It only shows what is in their line of vision. That is why the novel is about the "pools of darkness" in England. But the intense focus on the actions and the changing attitudes of the three men and the woman provide light, redemptive light -because salvation is in their sinews that refuse to give up, in their hope that does not flag and in their triumphant march that leaves behind old certainties.

Sahota keeps their conversations a little stilted, as Indian English often is. But there are times when the language turns, and evokes both coiled darkness and cascading light:

"She closed her eyes and bowed her head and brought her hands together on the plain wood of the table. She could feel her breath shaking inside her? No. No Him, him, no one, nothing. Only black silence and dead space. Her hands were trembling? Birds flew past her shoulder and crashed through the wall. A river rushed out of her chest. The words dried away. She raised her fingers to her head, to her turban. She lifted it off and put it on the table. She eased out the hairpin down by her neck and placed that on the table too. And the pin above that, and then pin after pin and clip after clip and all the while her hair was coming down in ribbons, loosening, uncoiling, falling."

Sahota shows us our side of England, the dark, brown England.

Follow the writer on Twitter @charmyh