As I write this, Green Book has established its position as a frontrunner – if not the frontrunner, thanks to Roma – for this year’s Best Picture winner at the Oscars. In certain quarters, that’s cause for concern. There’s a villain every year at the Oscars, at least in recent history, but with Peter Farrelly’s film firming as a real contender, it’s increasingly attracting the outrage once directed at Vice and/or Bohemian Rhapsody (though expect the latter to change with the long-rumoured details of Bryan Singer’s paedophilic peccadillos published by The Atlantic recently).

Without dwelling upon offscreen controversies, relevant though they are – Farrelly’s flashing, writer Nick Vallelonga’s Trump tweet, star Viggo Mortensen’s boneheaded attempts to explain racist representation – it’s worth unpacking why Green Book is so controversial. Fundamentally, this is a film of two halves, and one of those halves is only controversial as a Best Picture contender because of its banality.

Green Book, you see, follows the (sort of) true story of musician Dr Don Shirley (Mahershala Ali) and his driver, Tony Lip (Mortensen), a heavy contracted primarily for his ability to punch his way out of trouble. Shirley is touring the southern United States circa 1960s – necessitating the titular green book to determine the ‘negro-friendly’ restaurants and hotels to attend – and Tony is there to defend against the kind of issues you’d expect a black man to face in Jim Crow era America. One half of the film is a familiar, middlebrow road movie, which – in my view – mostly succeeds. The other half is more problematic, but we’ll get to that.

It’s no surprise that Farrelly could compose a crowd-pleasing road movie. He’s got the pedigree in the cruder comedies he directed with his brother, from Dumb and Dumber to Me, Myself & Irene. Here, he trims the dick jokes and bouts of gay panic for a more restrained interplay between the reserved, well-manned Shirley and the comparatively vulgar Tony. Maybe I’m just a soft touch when it comes to buddy movies, maybe it just speaks to the acting talent of Ali and Mortensen, but I found this half of the film effective, if unimaginative. Farrelly executes the material with aplomb, if not finesse, and the pacing is spot-on throughout.

Of course, if Green Book were merely a heartwarming buddy movie, complete with its treacly fake out of an ending, it wouldn’t be picking up five Oscar nominations and attracting short odds to take the big prize. What makes Green Book pique Oscar voters attention is, presumably, its self-imposed aura of importance in tackling race relations of five decades prior.

Since I’m already sub-dividing the film into its constituent parts, let’s go a step further by looking at the two ways Green Book deals with race: one blunt, clumsy but justifiable and the other mawkish and often offensive. In the first instance, I’m referring to how deliberately Farrelly frames Tony’s racism in the film’s first act. When a pair of black tradies attend his apartment, a cotillion of his Italian friends arrive to protect Tony’s wife’s (Linda Cardellini’s) honour, while the camera regards them with practiced caution. When Tony arrives to interview for the role of Shirley’s driver, both the camera and Tony pay careful attention to one other applicant in particular; he’s Chinese so of course, within minutes, Tony’s casually dropping racial slurs.

I don’t think it’s offensive to portray racism in this kind of internalised, perspective-of-the-oppressor way (though I understand why others might disagree). It’s a timely reminder of how central race was the social relations as recently as five decades ago, and how as much as middle class whites (like myself) might like to pretend we’re ‘post-racial’, this remains the reality for most – even if it’s more carefully disguised. The journey between Shirley and Tony, then, stands as an opportunity for Tony’s eyes to be opened to the realities of being a minority in America, someone subject to legislated discrimination by peers and police officers alike.

This brings us to the fourth, cancerous corner of Green Book’s foundation. It quickly becomes clear that the film is less interested in examining racism from a privileged – and oblivious – white perspective than pivoting towards facile solutions to racial conflict. Specifically, it hangs Ali’s character’s crisis of confidence on his inability to fit into either white or black society, exacerbated by his stuffy self-importance. Again – like a lot of things in this film – there’s potential here, but the execution is disastrous.

Farrelly and Vallelonga present ‘black culture’ as rough and raw, then go on to suggest that Dr Shirley – an immensely intelligent man – needs the insight of one Tony Lip to understand his own racial insecurities. This builds to a utterly wrong-headed conclusion, where – with the knowing assurances of Lip, who’s now apparently grown into a paragon of racial tolerance – Shirley stands up against smug racist southerners. It might not be a problem to portray racism through the lens of someone who’s never had to experience it, but to then to extrapolate that into a broad representation of how to ‘fix racism’ underlines the fundamental problems undermining Green Book.

Still, set all that aside, and what you have is a charming if forgettable road/buddy movie, anchored by a very impressive performance from Ali, who manages to sell even the clumsiest dialogue. It’s the kind of film that, had it not attracted such prominent attention from awards bodies, would’ve quickly disappeared into the slipstreams of history. Ah well; I’ll be rooting for Roma regardless.