There's a punishment handed out by sexual dominants, typically female ones, called ruined orgasm. The idea is to tease the submissive – bringing them close, then stopping, close, then stopping – until they can't take it any more and end up climaxing without being touched either by the dominant or themselves.

This contact-free orgasm is infinitely less satisfying than a conventional one, and that's why it's a punishment. You build a person's expectation for hours, days, sometimes weeks, and make them believe they'll eventually experience mind-blowing release. Then you let go and leave the orgasm to whimper out – it's an anti-climax, quite literally.

That, for me, is Fifty Shades of Grey – a ruined orgasm. Since E.L. James' novel was first shat into bookshops in 2011, its alleged eroticism has been discussed by columnists, talk-show hosts and punters around the world. But the screen adaptation is so tame, so timid, so giggly about its subject matter, it's impossible to take seriously as an erotic story.

I've honestly seen music videos that have turned me on more than this, and I'm one of those people who gets off on BDSM for real. Maybe that's the problem – maybe I'm numb to the castrated version of dominant/submissive sex that film censorship demands – but I think even outsiders are being left cold by this one.

I glanced around the cinema during each sex scene and not one person was wriggling in their seat, biting their lip or making out with their girl or guy. Everyone just sat – glassy, bored, limp. If the couples from the back row did go home and bang that night, I guarantee it had nothing to do with Fifty Shades of Grey.

I blame it on two things. First, Sam Taylor-Johnson's direction. I don't know to what extent she was bound by the BBFC, the MPAA, or whomever, but the sex scenes are uniformly truncated. Every time Christian and Anastasia get into it, Fifty Shades pulls back. There's plenty of nudity (at least, female nudity) and a couple of sequences where Christian whacks Anastasia with his hand or a flogger, but an uncompromising, full-frontal portrait of kinky sex this is not. It's all cuts and low-lighting.

Jamie Dornan and Dakota Johnson never have the chance to perform with one another – the film just dances between flash close ups of breasts to skittish half-glances of buttock, without ever settling to show the act itself. Is it because of censorship? Probably not, the more I think about it. Paul Verhoeven's movies are plenty explicit, so are David Lynch's, Ben Bertolucci's and David Cronenberg's, and they all pass through the studio system.

It seems like Taylor-Johnson is doing her best not to offend, to do, basically, what E.L. James did with her novel – use BDSM, and sex in general, as the seasoning on an otherwise trad romance story. You barely get a sense of passion, intoxication or even mild arousal on behalf of these characters and – without wanting to sound like a teenage boy, disappointed with the VHS he's just rented – it's because you never see anything.

Second to that, the aforementioned Jamie Dornan and Dakota Johnson simply don't give a toss about each other. There's nothing, not chemistry, not life, not even lust, holding their on-screen relationship together. Maybe Taylor-Johnson can't wholly be blamed for slicing up the sex scenes. Maybe once she had the rushes of these two actors, and could see the dead looks in their eyes, she had no choice but to chop together montages, just to inject some goddamn life. Again, all I see in these two performances is fear, or at least shame bordering on fear.

For what's supposed to be a bold, penetrating example of kinky sex reaching the mass market, everyone involved in Fifty Shades of Grey seems apprehensive. What pervades isn't a sense a liberation, like 'thanks to this film we can now indulge in BDSM, en masse, guilt free, for the first time.' It's more a sense of ignominy. It made me feel ashamed of myself. Dornan and Johnson's performances, lifeless and afraid, aren't the equivalent of a Kama Sutra, perched nonchalantly on a bookshelf – they're a vibrator, buried in an underwear drawer, afraid to come out.

And what this comes down to is a fundamental misunderstanding, both on James' part and the film-maker's, of what dominant/submissive relationships actually involve.

Fifty Shades of Grey
Jamie Dorman eyes up Dakota Johnson in Fifty Shades of Grey. Universal Pictures

Christian Grey isn't sexy – he's a psychopath. His idea of dominance is following Anastasia around, beating her with floggers and manipulating her into signing a contract that'll permit him to legally screw her whenever he likes. Her response, at least until the film's empty as hell conclusion, is simply to roll with all that, ostensibly powerless against Grey's good looks, and assurances that this will be good for her.

He's empty, unromantic and sexually joyless – she's clumsy, naive and totally receptive. This is not – repeat, not – what D/s couples look like, at least, not the healthy ones.

I've said it before: we're just like you. We go for dinner, we talk a lot, we fall in love, we do romance. The only difference between D/s and "vanilla" couples is that our sex is better, since we communicate what we're looking for and spend a vast amount of time refining the dynamic, making it work, making it pleasurable. This idea of 'man say, woman do, because this is fetishism,' is totally out of whack.

For one, the submissive men and women you meet are never frightened wee mice, waiting to be told – they're confident, assertive and out to get. Likewise, dominants, at least those who don't fall into the marginal psychopath contingent, the one that exists in any kind of dating, are considerate, nurturing listeners, not entitled creepmeisters like Christian.

Despite one flash of accuracy, where Christian says he started in D/s by being someone's submissive (a pretty standard route for most people) Fifty Shades of Grey gets the whole "scene" back to front. D/s, in this movie, isn't about compassion or mutual respect – it's not even about enjoyable sex. It's just a dispassionate display of power over a vulnerable other person, a sex crime committed in slow motion. No wonder the actors and director look so uncomfortable – no wonder the film doesn't arouse, entertain or liberate.

Ed Smith writes about games, films and culture for IBTimes UK. He has also written for The Observer, Vice, New Statesman and Edge magazine. Find him on Twitter @mostsincerelyed