With a running time of more than three hours — about 10 minutes shorter than “Jeanne Dielman, 23, Quai du Commerce, 1080 Bruxelles,” by recent acclamation the greatest movie of all time — “The Way of Water” is overloaded with character and incident. The final stretch, which feels somehow longer than the rest of it, runs aground in action movie bombast, and suggests that even a pop auteur as inventive and resourceful as Cameron may have run out of ideas when it comes to climactic fight sequences. There are a lot of those, in the air and underwater, fistic and fiery, sad and rousing, nearly every one of which will remind you of stuff you’ve seen a dozen times before.
That’s too bad, because much of the middle of “The Way of Water” restores the latent promise of newness — no small accomplishment in an era of wearying franchise overkill. Afraid that Quaritch and his men will bring slaughter to the forest, Jake and Neytiri seek the protection of Ronal (Kate Winslet) and Tonowari (Cliff Curtis), chieftains of a reef-dwelling Na’vi clan.
The differences among the Na’vi — physical as well as cultural — add an interesting new dimension to the anthropology of Pandora, and to the film’s aesthetic palette. The viewer discovers this variety in the company of the younger characters, especially Kiri and Lo’ak. Their adaptation to new surroundings — being teased for their skinny tails and clumsy arms, getting in fights and making new friends — gives the movie the buoyant, high-spirited sincerity of young-adult fiction.
Cameron’s embrace of the idealism of adolescence, of the capacity for moral outrage as well as wonder, is the emotional heart of the movie. You feel it in a horrifying scene of tulkun slaughter that aspires to the awful, stirring sublimity of the last chapters of “Moby-Dick,” and also in the restlessness of Lo’ak, Spider and Kiri as they try to figure out their roles. The next sequels, I suspect, will give them more time for that, but may also encumber them with more baggage.
I’m curious, and inclined — as I was in 2009 — to give this grand, muddled project the benefit of the doubt. Cameron’s ambitions are as sincere as they are self-contradictory. He wants to conquer the world in the name of the underdog, to celebrate nature by means of the most extravagant artifice, and to make everything new feel old again.
Avatar: The Way of Water
Rated PG-13. Almost blue. Running time: 3 hours 12 minutes. In theaters.