Twenty-five years ago, documentary-maker Steve James (along with producers Frederick Marx, and Peter Gilbert), had a sensational success with his engrossing and moving film Hoop Dreams, now on rerelease in the UK. It was his epic three-hour study of two African American boys from tough neighbourhoods in Chicago: Arthur Agee and William Gates, whose heartbreakingly open, intelligent, trusting and hopeful faces beamed out from the screen. James boiled down 250 hours of footage shot over five years, showing them growing up from 14 to 19 years old; both basketball-mad, both hoping for basketball scholarships to college and to a dimly perceived better life after that, maybe even being actual super-rich-and-famous basketball stars in the NBA.

Hoop Dreams received the kind of passionate response that Michael Apted had got for his Seven Up! documentary TV series or that Richard Linklater would later get for his real time coming-of-age epic Boyhood. It was famously championed by the legendary film writer Roger Ebert, who argued fiercely for it to get an Oscar nomination (James repaid the compliment with his own celebratory documentary about Ebert, Life Itself, in 2014) and Hoop Dreams struck a chord in the early years of the hopeful Clinton 1990s. It is candid enough about poverty, crime, drugs, fractured families and about racial tension, especially when Agee and Gates get a scholarship to the prestigious and predominately white St Joseph High School in Illinois, famed for its basketball and for its star alumnus, Isaiah Thomas. There is also a jaw-dropping look at a “basketball house” at a junior college: a very grim accommodation block reserved for basketball scholars (that is, black students) – a highly unfortunate, ghettoised institution.

But the film is not about racism as such; it is not angry and racist cops do not play a part, and there isn’t a rap soundtrack. Hoop Dreams was realistic but it certainly did not rule out the possibility of these boys simply and uncontentiously making a success of their lives through the classic route of college education — and of course sports are a huge part of that. It is that hope which unlocked people’s hearts in 1994 and will do so again I think in 2019, despite the fact that Googling these boys’ names for their situation now reveals something darker and more complicated.

Quite early on in the filming process, James must have realised that he had a great story on his hands: Gates and Agee got scholarships to the same posh school. But Agee’s schoolroom grades weren’t good enough – and he had to quit. But as his own family darkly hint: if he was doing better on the basketball court, then the school would have found a way not to worry about his fees. So poor Arthur has to go to a much rougher and more down-at-heel school, with his confidence having taken an almighty bash.

But wouldn’t you just know it: Arthur’s basketball prowess in this underdog school in an underdog team starts surging back up. Meanwhile, back at St Joe’s, things are difficult for William. Some things look different now. The TV show with cigar-smoking white sports reporters making their judgments on which kids are going to be big stars looked funny in 1994. Now there is something a bit seedy about it. Could James make Hoop Dreams now, in the age of #blacklivesmatter when the idea of “dreams” looks more naive than any time since the 1970s? Perhaps a white film-maker would be self-conscious of doing anything of the sort. But perhaps James’s biggest achievement is his unshowy emphasis on the poetry of basketball itself: the jump shot, the slam-dunk, ecstatic physical expressions of pure transcendental success.