I’m not sure I’ve ever really seriously thought about slavery before. In an abstract sense, yes of course, one knows that it is a terrible thing and that Wilberforce was a good man, but that merely scratches a tiny part of the surface. If I thought about it all, I would come up with the fact that you have no freedom, you work hard hours every day and probably have little to eat and drink and no real place to live. If I thought of slave traders, I would think of some fictional character like that in Le Corsaire, or 1001 Nights, something out of Kismet, or Up Pompeii. If I thought of their masters, I would probably envisage some mean ogre of a swine towering above a bunch of workers, threatening them with (but maybe not using) a whip. If I thought of the slaves themselves, I’m not sure what I would envisage; probably nothing more horrific than Paul Robeson singing Ol’ Man River. But having now seen 12 Years a Slave, I am ashamed of that ignorance.

This film paints a very different picture. I could not have imagined the sadistic relish with which the slave handlers whip and torture their slaves within an inch of their life – or if they went an inch too far, who cares. I could not have imagined the slave purchasing process, taking the wife and kids out dressed in their smart suits and crinolines, to inspect, prod, slap and humiliate naked men and women in someone’s fancy drawing room. I could not have imagined the sense of fear that meant that when your fellow slaves were being beaten, whipped or hanged you had no choice but simply to look away with no outward emotion. I could not have imagined that a slave would be required to whip another slave whilst their master and mistress ogled the process with glee. I could not have imagined the association of these vile landowner slave-owning families with adherence to their Christian God. I could not have imagined that the women were as happy to abuse their slaves as the men. I could not have imagined that you could buy a slave with a mortgage. I could go on.

This is not an easy film to watch. I underestimated the grit and determination that Mrs Chrisparkle and I would need to see it to the end. We are not used to watching violence, but the violence in this film is shocking, sadistic, visceral, graphic; yet perfectly justified. The personal tragedies that unfold on the screen split husband from wife and family, mother from children; and if these victims show too much emotion, or challenge an injustice, they die; disposed of as a no longer needed commodity, like a worn-out pair of pants; but not just slung away in a bin, ripped to shreds first.

I think one of the things that subtly emphasises the horror of this true story of a free black man in 1840s Saratoga, New York, who was tricked into being drugged and overpowered to be sold as a slave, is the fact that it is a very beautiful film. That irony is clear throughout – stunning cinematography, great acting, great costumes, beautiful sets, and a marvellous soundtrack. Those gorgeous captures of sunsets over the Mississippi are to die for; trouble is, uncountable thousands (millions?) of slaves did just that. It’s so striking that all this beauty is based on such ugliness; the immaculate and expensive Sunday-best clothes of the families, the stately residences and outhouses that the slaves build, are all at an inestimable cost of life and humanity. It made me want to go over to America, find some of those beautiful houses and torch them. Mrs C tried to pacify me by saying that previous generations have probably already done it.

Chiwetel Ejiofor puts in an immense performance as the formerly free Solomon, full of dignity and despair at injustice, perpetually hanging on to some distant hope that life remains worth living. Lupita Nyong’o is incredibly moving as the devastatingly abused Patsey, raped by her master, assaulted by her mistress in return, and almost flayed alive as a punishment for absenteeism to procure a small bar of soap, to which she pathetically hangs on during her torture. Michael Fassbender is very strong (in more ways than one) as the Biblically unstable landowner Epps and Sarah Paulson unnervingly brilliant as the vile Mrs Epps, of whom I could only say at the end, taking the words of Willy Russell’s Rita, “wasn’t his wife a cow”.

If you survive the 134 minutes of unrelenting misery (Mrs C’s description), at the end you feel flat, wasted, despairing of humanity, and guilty about your own freedom; well we did. Never has quaffing a superb Argentinian Malbec during a film, whilst luxuriating in the Errol Flynn’s fantastic leather seats, felt quite so shallow. For me, I accepted the film for what I take it was meant to be – a no-punches-pulled drama about the inhumanity of slavery. But Mrs C’s reaction was far more morose. The violence was just too much for her, and even if the film had decent motives, she couldn’t help think, what’s the point; there is still people-trafficking and slavery, there is still discrimination, prejudice and brutality against our fellow men; as a planet we have learned nothing about how to live as one. I could barely get another word out of her all night. So take note chaps, this is not a good movie for a date.

A very fine film, yes, and no doubt an important one too. But check your tick boxes before committing to it – it can make you feel desperately sad, much more than you would expect; with side effects of high-level anxiety, guilt and worthlessness that take between twelve and twenty-four hours before starting to pass out of your system.