That what I've come to the conclusion this is, its a Stand Alone Complex. The movie draws on original material and an original Plot which borrows heavily of elements from the Anime both seasons, and the animated adaptation to create its own story which even if you've never seen the original series or anime can still stand on its own merits, and if you have seen both you can recognize the elements added and how they fit.
The good:
Scarlet Johannsson: In my opinion she did a great job as the Major for this role and film. I think shes shown she can carry an action film on her own and I really hope Marvel gives her a Black Widow standalone movie soon.
The action: Solid though not breathtaking action all around including the movies final sequence not quite a rollercoaster ride but it does the job.
The Cast: Solid all around Cast each person handling their roles nicely and believably despite in some cases a lack of characterization. Still veterans of the series will see and recognize every character instantly.
The Bad:
Little dull and plodding. While it stands alone as a good solid action film worth an afternoons viewing it does drag in a couple spots, and lacks the deeper intellectual themes of soul and self realization that made the series and adaptaion movie such a deep ride.
In regards to the casting controversy, well frankly its non existent. Without spoiling lets say that ScarJo plays a Major for this film, which is not necessarily the Major we know, But its a good major for this adaptation. Motoko Kusanagi is in this film mind you before you panic, just not in the way you think.
Suffice it to say I understand where they were coming from with the casting and I don't hold it against them. The Majors ethnicity and nation of origin, and even gender are called into question throughout the anime and manga. And thus her appearance as a cyborg is quite frankly relative.
Still In an ironic way the way they do the character of the Major in this movie, takes the above and ironically inverts it on itself by making her origin and ethnicity known at a certain point.
Long story Short I recommend a viewing of the movie as a stand alone complex, and make your judgments from that. Theres enough for newer fans of the franchise to wet their appetites for more, and enough for long time fans to catch the relevant material from the 2 seasons of the anime, and the anime movie.
Just my two copper pieces.
*put on flame retardant kitty fur*
let the burning begin.
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