The story of a man who tried to be good “but then ran out of money”, Alfred Döblin’s classic novel Berlin Alexanderplatz has been described as a parable about the futility of ambition and morality in the twilight years of the Weimar Republic.

However, a cinematic reinterpretation premiering in Berlin this week finds more hopeful meaning, pondering if the capital’s seedy underbelly could give birth to a modern, self-confidently multicultural Germany.

In Döblin’s experimental 1929 novel, which has been likened to Ulysses, the protagonist, Franz Biberkopf, is a WW1 veteran freshly released from Tegel prison, where he served time for murdering his girlfriend. In Burhan Qurbani’s film of the same name, he is Francis [Welket Bungué], a migrant from Guinea Bissau who is the only survivor of an illegal crossing over the Mediterranean sea.

Qurbani, born in western Germany to parents who fled the Soviet-Afghan war, told the Guardian he was inspired to re-read Berlin Alexanderplatz, a set text at many German secondary schools, after moving to the capital.

“That’s when this idea of two parallel societies began to overlap,” Qurbani said. “The damaged first-world-war veteran and the refugee traumatised by his journey across the ocean, both of whom have the hubris to say: ‘I belong not on the fringes, but the heart of society’.”

In the novel, Biberkopf sells newspapers, vegetables and shoelaces before drifting into prostitution and organised crime. In the film, opening in Germany with a three-month delay due to the pandemic lockdown, Francis works his up way up the hierarchies of a gang in Berlin’s Volkspark Hasenheide, a 100-acre public green space in Neukölln district where dog-walking pensioners, wannabe acrobats and picnicking families coexist with a regimented network of mostly black men selling drugs.

“My dealers have style,” Francis’s mentor and nemesis, Reinhold [Albrecht Schuch], tells him. “No sales to pregnant women and children. Hipsters pay double. And pensioners get a discount.”

Where Döblin builds a literary montage out of Greek myths, folk songs, news reports and billboard adverts, Qurbani cites William Shakespeare, Hannah Arendt and Francis Ford Coppola. The film’s pivotal scene deliberately echoes the opening line of The Godfather: “I believe in America”.

“I am here: black, strong, fearless”, says Francis. “I am wearing an expensive jacket, I drive a German car, I have a German girlfriend. I am the German dream. I am Germany”.

When Rainer Werner Fassbinder adapted Berlin Alexanderplatz into a 14-part series for television in 1980, the enfant terrible of New German Cinema made the story of Franz Biberkopf’s short rise and long fall feel like a chamber drama.

Qurbani’s film, a UK release for which is currently being negotiated, aspires to the type of epic Hollywood cinema about migration into America told by Scorsese or De Palma – “gangster movies that hold up a mirror to society”, the German director said.

While critics have universally praised Qurbani’s ambition, some reviews have bemoaned the treatment of the novel behind the film: Die Zeit complained the director and his scriptwriter had managed to “erase everything that made their source material experimental, or challenging”, by investing too much of our hopes in Francis’ personal struggle.

“The true hero [of Döblin’s Berlin Alexanderplatz] is language itself, the babbling and madness, anonymous social events that swallow up the individual.”

Die Welt, by contrast, was convinced that Qurbani’s reinterpretation “is here to stay like Fassbinder’s”, describing the Portuguese-Guinean actor Bungué’s modern-day Franz Biberkopf as “neither a sneaky asylum fraudster nor a poor victim of globalisation”, but “a modern hero, who has to quickly pick up the rules of an unknown environment”.