The story proceeds by fits and starts with a narrative line — Alita’s journey of self-awareness — that is embellished with a dreary old-fashioned romance and regularly interrupted by chaotic action scenes. Some of this crash-boom stuff takes place during a game called Motorball, one of those survivalist contests that have been a genre staple since at least the 1975 film “Death Race 2000.” The contestants have something to do with Vector (a wasted Mahershala Ali), a regulation villain who takes fashion cues from “The Matrix.” This being a very small world, he lives with Ito’s ex, Chiren (Jennifer Connelly), who when not selling her soul lounges in garters and stockings.

Everything here tends to remind you of something else, including Alita, who was created with performance capture. This involves monitoring and recording a performer’s movements using sensors attached to her face and body, information that becomes the foundation for a character that’s digitally fleshed out. Cameron used a version of this technology to greater effect in “Avatar,” a reminder that whatever his limitations as a filmmaker — he’s a great visual storyteller who’s invariably easier on the eyes than ears — he is a technological wiz. Salazar’s performance, alas, is consistently bland, but then she was drawn and directed that way, like Jessica Rabbit.

It’s easy to imagine that both Salazar and Rodriguez would have fared better if her face had been left alone rather than rendered into a stylized manga cartoon, complete with a heart shape and eyes even bigger than Emma Stone’s. It’s vaguely diverting to stare at Alita’s face, at least at first, to ponder its shape, texture and pale color, and the way that her brow furrows when she’s being emphatic. Mostly, though, what’s interesting about it is that it lacks the conviction, the spark, which turns truly wonderful animated creations — Disney’s Pinocchio, Hayao Miyazaki’s Ponyo — into characters you laugh with and weep for. This is a matter of style, inspiration and imagination, or their absence.

There’s so little at stake in “Alita: Battle Angel” that it blurs into uninvolving spasms of visual and aural noise as it lurches to the cliffhanger ending, a setup for promised sequels. If you stick around for the end credits, you will read that “the making and authorized distribution of this film supported over 15,000 jobs and involved hundreds of thousands of work hours.” In other words, piracy threatens the American movie industry, even if a chunk of the jobs here seem to have originated outside the United States. It’s still a worthy wag of the finger, although it’s difficult not to wish that more of those hours had been spent telling a really good story instead of tweaking tech and shiny breasts.