Django Unchained has attracted well-documented criticism for its exploitation cinema-esque depiction of violence but its most serious flaw is a jarring juxtaposition of tones that completely undermines the film's purpose.
Quentin Tarantino's latest could have been a rewarding emotional experience, a cathartic metaphor for fighting racism, to give - as the director professes - African-Americans a hero in the Western mould.
Or it could have been a brutally sharp-witted comedy, a complete send up of people's attitudes to and ill-conceived views of racism, both at the time before the Civil War and in modern America.
But it attempts to be both, and inevitably fails to pull it off. The two tones simply do not interlock and mesh. We watch films to experience an emotional reaction, but Django blurs the lines too far as to render such a response.
One throwaway scene, where a gang of Ku Klux Klan riders on horseback quibble about not being able to see out of the eyeholes in the bags covering their heads is akin to something from an episode of South Park.
But the writers of that show keep the tone straight throughout and it is all the more effective for it. The message is clear.
In contrast, Django ultimately carries no message. We see horrific acts of racist violence against slaves but then two seconds later everyone in the cinema is in uproar because someone made a funny.
It all becomes overwhelmingly jarring, like Schindler's List crossed with Saturday Night Live. What emotional reaction are we meant to have to the film?
We see three dogs tearing a runaway slave's body limb from limb seconds after Leonardo Di Caprio's plantation owner Calvin Candie has poked fun at a slack-jawed yokel responsible for holding the beasts back, complete with pitchfork and drool falling from his lips.
Christoph Waltz's wisecracking Dr. Shcultz later recalls those horrific images and is rendered completely solemn, as the viewer should be, but each separate tone keeps undermining the other's attempts at creating sympathy and empathy.
Are we meant to laugh or cry? These two emotions are by no means mutually exclusive in films, but with subject material as serious as Django's any humour should most certainly be of the gallows variety.
It certainly should not be slapstick. The humour simply does not work, not when Django is making his horse dance after finally freeing his wife Broomhilda from years of horrific torture.
Not when the francophile Candie demands to be addressed as Monsieur Candie yet also gets angry when anyone actually speaks French to him because he is too stupid to learn it, before threatening to cave in Broomhilda's skull with a hammer.
Samuel L. Jackson's house slave Stephen is perhaps the most riling character in the film, an evil, maniacal man who tortures the female slaves under his charge, sent up and played for laughs by the actor and Tarantino as a comedic Uncle Tom figure.
His every line, muttering 'black ass' this et cetera, invites laughter but minutes after his introduction we see Broomhilda screaming in agony as she is removed from 'the box' - a horrific punishment dealt to her by Stephen for her attempt to run away.
But then everything is fine because Stephen asks the lingering Django, brought to tears by his wife's suffering, whether he wants to be shown to his room or sleep in the box. Cue more laughter, right?
All the humour just undermines the cathartic nature of the revenge Django takes out on Candie and co. Any true emotional payoff of seeing them all get their comeuppance is watered down because you don't know how to react to it.
Should we pump our fists because these evil bastards have got what's been coming to them? Or laugh because one of them is shot in his genitals?
Are we watching farce or something serious? The argument that by making the topic of slavery funny allows people to embrace it simply doesn't carry water, because no one is taking such a gravely serious matter seriously at all.
I'm reminded of those Youtube clips parodying dramas such as The Wire where someone has slapped a laughing track on a certain scene.
The canned laughter completely alters the serious tone of the clip, to comic effect.
That is Django in a nutshell - 2 hours and 45 minutes of it, to be precise.
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