Isn’t it curious. “Alita: Battle Angel” was much promoted before its release, but it was always referred to as the product of its director, Robert Rodriguez.

Certainly the great action director has built a reputation with real movie fans. His feature films include “Desperado,” “Dusk ‘til Dawn,” half of “Grindhouse,” the “Spy Kids” movies, “Machete” and “Sin City.”

But what the ads didn’t mention was that the movie was co-written by Canadian James Cameron, the multiple Oscar winner who wrote and directed “Avatar,” “Titanic” and “Aliens.” We had gotten the idea that Cameron products were sure box office.

For “Alita” he was working from a “graphic novel” by Yukito Kishiro. And given how fundamentally flawed this screenplay is, Cameron and fans everywhere of comic books may think it just as well that Rodriguez, whose direction here is stellar, gets all the attention.

It isn’t even that the script in general is so awful, though the dialog seems always to be perched on the lip of disaster. The problem is that the story loses track of its central complication — that a massive injury has kept its title character from knowing her own past. And, then, it doesn’t help that the character motivations are as difficult to discern as are those in soap operas.

When can the characters trust whom? In the film’s closing sequence, someone who ought to know better is risking everything on the promise of the film’s villain. By the way, we don’t learn how that gamble turns out. And how human does a cyborg have to be to fall in love?

Not that Cameron hasn’t seen “Blade Runner,” the movie which specifically addresses this last question. Rainy “Blade Runner” and “District 9” (for the tethered space ship) and “The Hunger Games” and “Roller Ball” and so on — “Alita” gets ideas from all these sources to end up with a story quite close to the one in “Captain Marvel,” a movie which actually came out after it.

In both movies our heroine has fabulous powers, brought from space to Earth. Badly hurt during action, she is brought back to life by a man who seems to want to limit her behavior. Eventually she gains her independence and attacks an evil that should be too strong for her to overcome it.

That describes both “Captain Marvel” and “Alita: Battle Angel.” But we don’t ever learn who wins Alita’s war with the hovering spaceship-dwelling Nova, who can take over the faces and voices of his associates on the ground in the film’s post-apocalyptic Mexico City.

So the rarely-seen Nova, for reasons we can only argue over, keeps interfering with surface law enforcers (“Hunter-Warriors,” almost all of them at least part mechanical). He also seems to control the city’s big pro roller-derby series.

Are you with this so far? Because some viewers are going to be completely lost. One can understand why kindly Doc (Christoph Waltz, who has won two Oscars) and his ex-wife (Oscar winner Jennifer Connelly) try to help the title cyborg. Why Vector (Mahershala Ali, who has won two Oscars) is so calculating and yet credulous is anybody’s guess.

And then there’s the central love story. Cyborg Hugo (Keean Johnson) is a sort of Aladdin character. He and Alita (the always computer-animated Rosa Salazar) seem to fall in love. Can machines be in love? To what extent are the two of them machines? Is hormonal, teenaged, romantic love a real pitfall for the manufactured?

The problems in “Alita” aren’t the fault of the actors. And Rodriguez has done everything humanly possible to keep us interested in the film, cutting skillfully, constantly introducing new computer-generated settings and cyborgs and action sequences, and making the most of the story’s few feints towards giving its steadily unfunny characters some little touches of humanity.

For me, the director’s exertions weren’t enough. For many moviegoers, folks who are more enthusiastic about the look of a film and the pace of a film than they are in the storytelling, “Alita: Battle Angel” is going to be satisfactory.

But James Cameron isn’t going to be winning any awards for this gem.

Recommended for you