(MA15+) 3 out of 5

Director: Sam Johnson-Taylor.

Cast: Dakota Johnson, Jamie Dornan, Eloise Mumford, Max Martini, Jennifer Ehle, Marcia Gay Harden.

I CAN'T believe I'm saying this, but the film adaptation of Fifty Shades of Grey is far better than it has any right to be.

Don't get me wrong - it's not great. But it's not terrible, which is what I was honestly expecting.

Given that the source material is a novel that began life as a piece of kinky Twilight fan fiction which was "dull and poorly written" (New York Times), "a sad joke" (Huffington Post), and "made Twilight look like War & Peace" (Sir Salman Rushdie), and which I've regularly heard derided as rubbish by people who've read it, my hopes were not high.

So it's a pleasant surprise that the film version of a book that spawned the term "mommy porn" and did more to boost handcuff sales than a police-themed dress-up party is reasonably solid, especially for a movie that is essentially plotless.

That's the main issue here - Fifty Shades of Grey is beautifully shot, well performed, occasionally funny, and weirdly intriguing but the thrust (ahem) of its story is basically "boy meets girl, boy whips girl, the end".

There are lines of dialogue that hit the ground harder than a broken bed ("I'm 50 shades of f**ked up," Christian Grey in all seriousness as if that's a common phrase), and the film edges into melodrama too often.

It's also tempting to criticise its tendency to mistake "creepy" for "romantic" but I figured that was kind of the point of the whole thing. After all this is a film that exchanges love for whips and chains and has two confused characters trying to meet somewhere in the middle.

Instead of a plot, we get a character study of a shy girl-next-door-type named Anastasia Steele (Johnson) and a sensitive-new-age-Patrick-Bateman-type called Christian Grey (Dornan), as well as an exploration of the sexual world of dominants and submissives.

Johnson is great and its her performance that's the most impressive aspect of the film, given that its her character's conflict that drags you along. Ana's transformation from Plain Jane Wallflower into someone who is questioning what they want and what they're willing to sacrifice to get it is compelling, as is her balance between naivety and inner strength.

Dornan is less impressive but could have been worse considering how poorly written his character is in places - given the strangeness of the subject matter (man wants woman to be his contracted sex slave) it's no wonder the script creaks under the weight of trying to explain his motives while keeping him likeable.

For all the film's faults, I can't help but feel that if this was subtitled and in Polish or French or something, then critics would be losing their collective shit over it, awarding it four and five stars for its examination of unconventional sexual peccadilloes, un-Hollywood-like denouement, and its eschewing of traditional plot techniques in favour of character exploration and inner personal journeys.

While I was totally prepared to unleash my poison pen at this film, I have to admit that was probably premeditated snobbery on my part and I can't help but wonder how many of the bad reviews it receives will be because of critics unwilling to concede it's not that bad.

Let me reiterate - it's not great. It's a bit hit and miss (pardon the pun) and it's climax (sorry) will leave some perplexed.

It's definitely not as sexy or as explicit as people might think it to be, but again, I figured that was kind of the point. This is about a relationship that is basically contractually agreed-upon domestic violence.

I suspect the writers and director have dug through what was essentially an elongated Penthouse Letter Of The Month and come up with a disturbingly engaging tale about loss of innocence that serves as an allegory for spousal abuse, and in that sense, it's an intriguing film.

Or am I missing the point?