Everyone knows that “Fifty Shades of Grey” originated as “Twilight” fan fiction by author E.L. James, but far fewer probably guessed that the movie adaptation would play exactly like a sequel to the vampire series, with deadly dull talk about S&M replacing endless consternation over turning into one of the undead.

This movie is about as stimulating as a cold shower, in which the one-dimensional Anastasia Steele (given more intelligence than she deserves by Dakota Johnson) and Christian Grey (Jamie Dornan) mope around while the former tries to decide whether to become the latter’s submissive.

That’s the whole show folks, all there is to it, and if that sounds like the recipe for a hot time at the multiplex I’ve got news for you: It really, really isn’t.

James, director Sam Taylor-Johnson and screenwriter Kelly Marcel fundamentally misunderstand eroticism; there’s nothing sexy about a relationship between characters who are total blanks beyond the fact that one would like to tie-up, spank and whip the other.

Their relationship plays out like your everyday supermarket lit romance if one half of the duo was a repugnant creep; the billionaire Christian stalks college student Ana, hounding her with texts, following her across the country, showing up to “rescue” her from an outing with her friends. He begs with her to please, please “try things my way,” while Ana responds by pleading with him to “let her in” emotionally.

The interior component is missing; there’s nothing in Ana’s story that begins to suggest why she’d agree to so much as consider letting this man completely take over her life. We don’t learn much about her at all beyond the fact that she a) majors in English literature, b) works in a hardware store and c) would, again, really love it if Christian would just “let her in.”

When it comes to Christian, the movie can’t be bothered to so much as explain the function of his slick, faceless corporation. He’s got a bit of a rough past and he doesn’t particularly like his family. That’s all we’ve got.

The actors have no chemistry whatsoever, further undercutting the eroticism. Johnson at least seems to be playing a real person, giving Ana depth that isn’t on the page by regarding Christian and his ideas with a healthy degree of cynicism.

Dornan succumbs to Christian’s robotic stiffness. The star can’t do anything about the ridiculously on-the-nose dialogue “More like fifty shades of [expletive] up,” being the most famous example, or the fact that the character is forced to brood at the piano repeatedly. By never finding a way to undercut the stupidity with a degree of humanity, however, or to even seem to particularly like Ana as more than a sex object, he re-enforces the character’s alien weirdness.

Taylor-Johnson is a gifted photographer making her second film (the first, “Nowhere Boy,” is quite good) and her talent shouldn’t be questioned. She’s simply victimized by an inability to escape the cold “Twilight” aesthetic; defined by sleek overcast Pacific Northwest exteriors and the impossibly polished marble floor and glass walls of Christian’s penthouse.

The sex scenes flop because of the movie’s total failure to suggest a genuine connection between these characters – as far as we can tell, Ana wouldn’t even be in the same room as Christian if he didn’t throw lavish gifts at her – and because the whole thing feels so corporatized. Bondage should be messy and confusing, reflecting the complexities of human sexuality and touching on deep-rooted psychology. The movie “Secretary,” with James Spader and Maggie Gyllenhaal, got this right. In “Fifty Shades of Grey,” it comes across as tame role play.