Opening Friday, the film adaptation of E L James’ best-selling erotic love story, “Fifty Shades of Grey,” launches what likely is Hollywood’s next blockbuster film series.

Like “The Twilight Saga” and its tale of a forbidden love shared by a human girl and vampire boy, “Fifty Shades of Grey” has its parallels with “Beauty and the Beast,” not to mention “Cinderella” and “Dr. Jekyll and Mr. Hyde.” That which is forbidden, taboo and dangerous is all the more tempting.

“Fifty Shades of Grey” and its two sequel books, “Fifty Shades Darker” and “Fifty Shades Freed,” have sold more than 100 million copies in 52 languages. Such “Twilight Saga” and “Harry Potter” numbers obviously tempt movie studios.

Despite its romance novel foundation, James’ tale of a virginal college student, Anastasia Steele, and the handsome, 27-year-old billionaire she meets by chance took soft-porn mainstream. Now the film adaptation, likely the first of four films to be milked from James’ three books, is poised to lure people to movie theaters, just as previous exploitation-gone-mainstream films “9½ Weeks” and “Basic Instinct” did in decades past.

Helmed by a female British director, Sam Taylor-Johnson, “Fifty Shades of Grey” melds romance novel ingredients with classic fairy tale and erotica. James, the books’ author, is also female. Adding the story’s female principal, Ana, to the mix, confirms “Fifty Shades of Grey” purpose as romantic-erotic fantasy entertainment designed by women for women.

On screen, the first installment of Ana’s and billionaire boyfriend Christian Grey’s steamy courtship and gamesmanship has its amusing moments. Grey, for one, habitually appears out of nowhere, like a silent, stealthy cat pursuing unwary prey. He startles Ana multiple times, just as the beautiful vampire Edward Cullen startled high school student Bella Swan in the “Twilight Saga” movies. The film’s funniest scene, though, features Ana mocking her suitor’s passive-aggressive tendencies. After the latter bright spot the film slips into a less entertaining quagmire.

But then what average young woman wouldn’t want to be stalked by a gorgeous, generous, alluringly enigmatic, unobtainable billionaire? Actually, it’s not that simple.

Christian is a dark prince with a troubled history. And he broods. Despite the vast control and power Christian wields in the surface world, he’s but a poor little rich boy in the dark corners of his soul. Unfortunately for drama’s sake, when Christian reveals the sordid details to Ana, they fall with a shallow clink.

Dakota Johnson stars as the initially nerdy, clumsy Ana. She meets the super-confident Christian, coolly played by Jamie Dornan, after her journalism student roommate gets the flu and can’t do a scheduled interview with the billionaire. Substitute interviewer Ana drives from Portland to Seattle, where she questions Christian in his towering Grey Enterprises building.

The remarkably naïve Ana obviously is not qualified to interview a school crossing guard, much less the imposing Christian. Shortly after he says he enjoys “various physical pursuits,” Christian turns the session around, saying, “I’d like to know more about you.” Suddenly, the man who can have anything and anyone is fascinated with the mousey little Ana.

Let the game begin. The question of whether Ana will play along with Christian’s sadomasochistic tastes becomes a central point of tension. There’s another question in just who is freeing whom from which inhibition?

Tapping into Ana’s desire to be strong but also save Christian, her conflicted prince, “Fifty Shades of Grey” delivers a trashy fairy tale full of flesh. Shallow pop psychology, Christian’s control-freak behavior and predilection for sadomasochism all figure in Ana and Christian’s war of wills and desires. Johnson, especially, plays the game well in her role as Ana, but there’s no escape from the silly, pulpy predictability of “Fifty Shades of Grey.”