Should you have four hours to spare any time soon (unlikely, but still), there are worse things you could do than grace Once Upon a Time in America with your attention. If it sounds vaguely familiar, that may be because Italian classical singer Andrea Bocelli recently duetted with pop singer Ariana Grande on a fairly successful interpretation of a famous piece from Ennio Morricone’s original score for the movie. The song is very lovely, but does slight justice to the original in context. Morricone is a film composer of deserved erudition, and this is, arguably, his most devastating score.

But there are other reasons for visiting this movie besides wanting to access Morricone’s musical arrangements.

Put simply, to visit and revisit Once Upon a Time in America is to aid its healing process — a collaborative effort that has been underway for over two decades now. The movie is one of the most tragic cases in cinema history; its production/reception and its fraught, fragile relationship with time outside the film only helps to colour the thematising of time that goes on within the film, making it, especially in context, one of the most painfully beautiful works of art in western cinema.

It began life as a passion project of the grandest, most Italian kind, as befits a movie directed by Sergio Leone, who is perhaps better known for adding his particular brand of glamour to ‘spaghetti westerns’ like Once Upon a Time in the West and The Good, The Bad and the Ugly. It was, in fact, to be his first and only venture away from that genre. Leone spent seven years fomenting his translation Harry of Grey’s book, The Hoods. It was his last movie; upon its completion and release, he retired from the business and died shortly afterwards. That he never lived to see the movie rehabilitated and restored to some of its former glory (the film re-premiered at Cannes in 2012, thanks to the painstaking efforts of committed cinephile Martin Scorsese) only adds to the peculiar poignancy of its story.

The film is a gangster film, although that definition should be used cautiously; yes, it is a movie about a small brotherhood of Jewish mobsters who make it big, and lose it all, in prohibitionera New York. But to paraphrase what Jean Baudrillard said about the U.S.A.: only non-Americans can actually “see” America for what it really is, and, more crucially, isn’t. Leone was not born and raised in the States the way that, say, Scorsese was, and so his America is product of a romanticising outsider’s imagination. Despite its cold brutality in some places, and its sheer violence in others, there is an ineffable quality to this movie which largely obscures the criminality of the main characters from view.

Instead, Leone communicates an eloquent love letter to that concept which he, as a European, could appreciate but never wholly grasp — the American Dream. Its fatalities and flaws are rendered as beautifully as its ideals. For Leone, the American Dream is mediated by and intersected through friendship, family and loyalty, and so what we get is not a gangster film so much as a film about a gang. It is unlike any other movie in its genre; in fact, it is barely of its genre, and perhaps one of the best genre films ever made because of that. Had the fates not intervened, and Once Upon a Time in America gotten the recognition it deserved, it might have even eclipsed The Godfather and reigned the landscape of mobster films.

Tonini’s cinematography is lyrical and hazy, just like the music and just like memory itself: the central motif of the whole film. Starring Robert de Niro as Noodles, James Woods as Max, and Elizabeth McGovern as Deborah — with a teenage Jennifer Connelly in her breakout role as McGovern’s younger self — Once Upon a Time in America obsesses over the implications and biases of time throughout. De Niro’s elderly protagonist arrives in New York with a mystery invitation after several decades’ absence; in extended flashbacks, which become a theme in their own right, the man’s life, from childhood through to twilight years, is more or less comprehensively conveyed. Regret, growth, change, return: all become the fabric woven into the movie’s tapestry. It’s indulgent, but not irritatingly so. Pauline Kael called it kitsch, but she said it in a way to suggest even kitsch has its merits.

Yet, ironically, that flashback structure — the central hinge upon which the film hangs its meaning — was denied the film upon its entry to the US (it initially debuted a ‘European cut’ which had already excised over two hours’ of Leone’s footage; the director deemed this version an acceptable contraction of his epic vision). The Ladd Company, who were distributing the movie in the States, went against the director’s will and shaved down those 220+ minutes to a meagre 139; they also distorted the sequence of the film to give it a more linear structure. Through attempts to make the order of things more logical, they effectively annihilated everything the film stood for. Kael called it “one of the worst cases of [film] mutilation” she had ever seen; certainly the movie bombed at the box office, and it never recovered the gravitas its initial European cut deserved — at least not until many years later, and with Leone too long gone to see it.

The scars may never fully disappear, but one likes to think the movie’s wounds have largely healed by now: the restoration was met with great enthusiasm from cinema enthusiasts and professionals alike, and the movie’s quiet cult following over the decades has ensured its blossoming into a contender on many “greatest gangster movies” lists. Yet the cautionary tale of both the movie’s interior and exterior history dances through it like a spectre that cannot disappear: time, always, is running out.