Much was made of James Cameron’s 2009 passion project “Avatar,” a $240 million cinematic (or is that computer?) revolution that mixed live-action humans with 10-foot, blue-skinned humanoids called the Na’vi, an indigenous race on the distant planet of Pandora (don’t open that box!). It was a grand, opulent immersion that scored nine Oscar nods, with wins for Visual Effects, Art Direction and Cinematography, and made nearly $3 billion worldwide, the most by a movie, ever! It was also a fairly flat revisionist fable: White man who is part of the invading forces switches sides, embeds with the technologically inferior natives and leads them to a victory that otherwise could not be achieved – “Dances with Wolves” (1990) circa 2150.

The militarized mining force that devastated Pandora’s ecosystem in that first “Avatar” chapter went by the moniker of the Resources Development Authority, a corporate, colonizing NGO bristling with annexation ’roid rage. The “oorah” mentality fueled and led by Col. Quaritch (Stephen Lang) felt right out of central casting, Snidely Whiplash simplistic without a nod or wink. In the new “Avatar: The Way of Water,” that limited two-dimensionality – and Quaritch – are back, and ready to rumble. What’s at stake this time? Pretty much the same as the last time: the ways and existence of indigenous folk and a delicate ecosystem with which they share a sustainable, symbiotic relationship. The big changeup in “Way of Water” is the milieu for the showdown and the resource the colonizing forces covet; instead of “unobtainium” and the planetary neural net that the Na’vi can plug into via their USB-enabled hair cord, it’s the water-world side of Pandora and the juice from a whalelike creature’s brain that can ease aging in humans.

Jake Sully (Sam Worthington), one of Quaritch’s grunts who last time around earned his pay by having his consciousness transferred into a Na’vi body to act as an RDA envoy, is back to lead the water Na’vi against Quaritch’s Sky People (any affiliation to Skynet?), named so because of their flying and now wave-riding war machines. Jake and Quaritch (seen shot full of arrows last time, now in Na’vi form too) don’t need liquid-filled tanks to lie in for the avatar process; they’re full-on Na’vi, and Jake’s married (funny how earthly traditions span galaxies) to love interest Neytiri (Zoe Saldaña), who taught him the ways of the Na’vi and Pandora. Between the two films, they bore a small brood. Also in the mix as young Na’vis are veteran actors Kate Winslet and Sigourney Weaver, who have worked with Cameron in the past – Winslet on that other water adventure (“Titanic”) and Weaver on “Avatar” and “Aliens” (1986). There’s even a Tarzan-clad human named Spider (Jack Champion) running around with the Na’vi teens.

Visually, the film is stunning, more so than the last, though you can’t escape the fact that it still looks like a video game running on the greatest graphics card of all time. I saw it in 3D Imax and suggest any fan champing at the bit do the same – it’s worth your greenback. The film cost nearly $340 million to make, and for about every $2 million you get one minute of Cameron’s obsession.

Keeping in mind that it took 13 years between the original and “Way of Water,” there are another three “Avatar” sequels on the slate. The sad thing is that the series has already begun to feel a bit like Peter Jackson’s “Hobbit” films: indulgent and long, with flabby, uninspired – recycled is more like it – dialogue. It’s too bad, too, because Cameron has taken concepts such as “Terminator” (1984) and Ridley Scott’s “Alien” (1979) and shepherded those concepts in fresh, new ways.

I did sit through the whole three-plus hours fully engaged, marveling at the effects and the imaginative designs, but when I walked out I felt Camron had just told me the exact same story, and all he did was just add water.

• “Avatar: The Way of Water” is at Landmark Kendall Square Cinema, 355 Binney St.; Apple Cinemas Cambridge, 168 Alewife Brook Parkway, Cambridge Highlands near Alewife and Fresh Pond; and AMC Assembly Row 12, 395 Artisan Way, Assembly Square, Somerville.

Cambridge writer Tom Meek’s reviews, essays, short stories and articles have appeared in WBUR’s The ARTery, The Boston Phoenix, The Boston Globe, The Rumpus, The Charleston City Paper and SLAB literary journal. Tom is also a member of the Boston Society of Film Critics and rides his bike everywhere.