Now a lot of those films feel quaint and kitsch. It's hard to imagine Waters making a film today that could cause the same level of offence, although he protests that his early works still possess some shock value for newcomers. “I don't know if they're that quaint. Pink Flamingos still works. I think if you're 20 and see it for the first time, it didn't mellow that much.” He does concede that his sensibility is more mainstream these days, however. “The kind of humour I did is now American humour. It’s normal.”

If Easy Riders, Irreversible and Pink Flamingos no longer generate outrage however, then there is one of the aforementioned ‘shock films’ of old that is even more shocking than when it premiered – and that fact speaks volumes about our shifting values. That is The Brown Bunny.

It wasn't simply the nature of the graphic scene itself that offended at the time. Viewers were also concerned with Sevigny having to submit so physically to the will of the director, as well as the fact that the unsimulated nature of the sex act arguably crossed the line that distinguishes cinema from pornography.

At heart, the transgression of The Brown Bunny is not the sexual content in itself. It’s the power relationship involved. The potential for real-life, but invisible exploitation behind the scenes has, rightfully, become much more shocking to us than anything that we can see on screen.

Where other films’ notoriety feels of its time, the outrage The Brown Bunny caused feels like a precursor to today. From the growing awareness of exploitation behind the scenes in the industry, to the rise of identity politics and the debates over representation, shock and offence in cinema is now less visceral, and more ideological.

For example, Tarantino was attacked for his use of the N-word in The Hateful Eight while the violence in his films has been seen as increasingly controversial, specifically that which is directed at women.

Meanwhile casting decisions regularly cause representation storms – from Emma Stone and Scarlett Johansson playing Asian characters in Aloha and Ghost in the Shell to Johansson originally being cast as a trans man in the now-postponed Rub & Tug.

And old movies continue to inspire new shocks from generation to generation. Ace Ventura: Pet Detective now seems transphobic because of the way it makes a trans female character a figure of monstrous humour, and Dumbo can’t be watched without balking at Disney’s decision to feature jive-talking crows – the leader of whom is called ‘Jim Crow’.

The concept of shock in cinema has changed – because it’s what audiences feel rather than what they see that governs what causes outrage. Which is why filmmakers may be perversely happy to see such an extreme reception for a film like The Painted Bird: at least it shows that there is still a more edifying way for cinema to shock audiences – through the visual image itself.

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