Minnie Driver, Gugu Mbatha-Raw and Nate Parker star in this drama about a superstar singer and the young police officer who helps her to find her own voice. (Relativity Media)

A shamelessly entertaining mash-up of “Gypsy” and “The Bodyguard” finely tuned to the blingy excess of the hip-pop era, “Beyond the Lights” is a movie brimming with promise and unexpected pleasures. Structured as a conventional stage-mother melodrama, this go-for-broke backstage romance, written and directed by Gina Prince-Bythewood (“Love & Basketball”), admittedly suffers from inertness during its most starchily emotionalistic passages. But it also fully owns its wish-fulfillment fantasies of love, fame and ambition, set within an overarching bid for authenticity that gives what might have been a disposable piece of eye candy an admirable sense of groundedness.

The fact that the film’s star, Gugu Mbatha-Raw, delivers a genuinely galvanizing performance as a singer searching for her own voice makes “Beyond the Lights” not just enormous fun to watch but surprisingly gratifying on an artistic level. Like the early Oscar hopeful Eddie Redmayne in the far more high-minded “The Theory of Everything,” also opening locally this week, Mbatha-Raw undergoes an astonishing physical transformation in service to the role of a young British prodigy. The fact that “Beyond the Lights” proudly occupies a middlebrow genre means that Mbatha-Raw will most likely be overlooked for the season’s biggest awards, the casualty of snooty high-low distinctions that, with luck, will mean nothing to audiences who like their pulp escapism served with smarts and good taste.

Mbatha-Raw plays Noni, who throughout her childhood has been pushed into stardom by her ruthlessly driven single mother, Macy (Minnie Driver). After a painful prologue when Macy cruelly forces 10-year-old Noni — beautifully portrayed by India Jean-Jacques — to “chuck” a second place trophy she’s won in a South London talent competition, we meet doe-eyed, lavender-tressed Noni all grown up, gyrating lasciviously in a music video and wearing heavy gold chains to accept her first Billboard Award.

The symbolism of those chains, like everything else in “Beyond the Lights,” isn’t subtle. But restraint is completely beside the point in a film that luxuriates as much in the outlandishness of its imagery as in the fairy-tale nature of its narrative. When Noni has a pivotal episode with the off-duty Los Angeles policeman guarding her hotel room, the encounter sparks a romance. But it also awakens a sense of self-worth that’s been latent while her mom-ager has been urging her to do whatever it takes to be famous, whether that means disrobing at the drop of a flash bulb or hooking up with a label mate for some easy publicity.

Driver brings furious, snapping vigor to her role as a postmodern Mama Rose, her prominent jaw seeming to reset with more determination each time Noni dares to challenge her master plan and manipulations. The LAPD cop, named Kaz, is played by Nate Parker with just the right mix of muscularity and quiet focus. Kaz has his own parental drama, in the form of a dad (Danny Glover) with just as many hopes and dreams for his son as Macy has for Noni. (The young man is such a Boy Scout that he steps on one of his own theatrically dramatic moments by insisting Noni put on her seat belt.)

Filmed with the lavish, invidious production values of an extended music video, “Beyond the Lights” looks and sounds terrific, its images of showbiz luxury and profligacy — including an eyepopping Beyoncé-like performance at the BET Awards — seducing viewers but also forcing them to question their own tastes for hyper-sexualized, often misogynistic, images of female artists. Prince-Bythewood cannily has her cake while eating it, too, by expertly choreographing those familiar strip-tease-like routines, only to turn the tables abruptly at the most meaningful moment.

She turns the tables yet again when Noni and Kaz make an impulsive decision that literally takes “Beyond the Lights” in a new and unexpected direction. That’s also when Mbatha-Raw, who starred earlier this year in the costume drama “Belle,” begins a chameleon-like make-under that not only reinforces Prince-Bythewood’s points about identity and integrity, but proves how an accomplished actress can make or break a story that by definition teeters perilously on the brink of sheer ridiculousness.

Everyone in “Beyond the Lights” brings admirable seriousness to otherwise stock roles, but it would be for naught without Mbatha-Raw’s honesty and intensity, which result in a star turn as compelling as any this year. The fact that “Beyond the Lights” is so effective at both celebrating and critiquing extravagance and artifice can be credited to Prince-Bythewood’s shrewd understanding of the highly pitched cinematic vernacular she’s working with. Even more crucially, when it came time to cast the transformational figure at her fable’s center, she found the real thing.

★ ★ ★

PG-13. At area theaters. Contains sexual content including suggestive gestures, partial nudity, profanity and thematic elements. 116 minutes.