Just saw it.
Non Spoiler review :
It's a pretty good action movie overall, perhaps not great, but it has good pacing.
The story is set somewhere in the 2500's and features a dystopic future, but of an unusual kind, where the haves don't seem to go out of their way to be mean to the have nots. It's kinda refreshing in many ways. It's more like a "We don't really care" type situation.
Life in Iron city isn't too bad, it's pretty much like many a large metropolis in our world today, with plenty of nice places to live, but also some streets you don't want to be caught out at night in.
Dyson Ido is a cyberdoctor and while looking for scrap parts he finds the head and torso of a cyborg, in some kind of stasis. He rebuilds her and they quickly bond in a kind of father - daughter relationship for she has no memory of her past. Alita is a blank slate, but not for long because her past catches up and reveals she is much more than just the sweet little girl Ido wants her to be.
Her path to finding out who she was and who she is now crosses that of many others and the various layers of Iron City are revealed over time.
The CGI is sometimes uneven, she looks quite off in some scenes, but they nail her in others. She's a very well developed digital character, and she reminded me of the excellent work they did on Gollum.
Another feature I liked is that she seems to have mass and momentum, she doesn't effortlessly leap through the air, you feel she is using power, fighting gravity as she moves.
Salazar nails a perfectly believable performance of somebody who may look like a tiny girl, but is in fact a powerhouse, but also has heart and humanity.
Even if you don't know Alita, it's a perfectly fine SF action flick.
*** Spoiler warning ***
*** Spoilers ahead ***
Kishiro's Manga is like Russian dolls, the more Alita discovers about her past the wider the universe she inhabits becomes. What seems like a simply mad-max style futuristic dystopia is merely the tip of the iceberg. In the manga Earth is nothing much than a backwater to a collection of transhuman societies, next to which being a nanotech enhanced plasma wielding cyborg is so passé.
Most simple humans can achieve immortality as long as they find the means to achieve it, but it's a dog-eat-dog society all the way and what may seem like a paradise is in fact more often a dead-end. The real evil is at the very top where people who have transcended humanity have lost all traces of it and people like Alita end up being the catalyst to dramatic changes.
The movie tries to tell the story of the first four volumes, and there is a lot of great material that didn't make the theatrical cut.
It manages reasonably well to streamline the story and retains many of the main elements of the manga. In some cases the characters are even slightly improved over the ones from the manga, adding a bit more depth to some.
It remains quite faithful to the manga in spirit, something Ghost in the Shell didn't dare to do for fear of alienating the audience. Though Alita is very dense and researched it's less hermetic and meta than GitS.
It suffers from too many antagonists, only to reveal one master puppeteer in what might be one of the most crazy evil people in the history of movie if done right, Nova or Destiny Nova in the manga, a mad scientist that is equal parts Mengele, Rick Sanchez, Hannibal Lecter and Scorpius, obsessed with challenging fate and the universe itself, experimenting with people, transforming them into his lab rats, but fascinated by Alita and becomes her sometimes ally, sometimes nemesis, in an attempt to see how far her destiny will carry her.
I do hope they will release an extended version that fleshes out some of the characters and adds more detail to an already very dense film.
Some people complained that Alita is all too perfect and that nothing is a challenge, but she does end up facing many challenges to overcome and the movie very rightly highlights that while she may be nearly impossible to defeat at this point, she remains emotionally vulnerable and the people she loves are also an achilles heel.
Overall they did a decent job of adapting the manga, sometimes missing a point here, but really doing it better than the original on others. It's not a perfect movie, but as an adaptation it was much better than I feared.