The original movie has a reputation for being forgettable, despite its nearly $3 billion worldwide gross (see: Slash Film’s piece from earlier this year, “How Avatar Became The Most Popular Movie No One Remembers”). Perhaps sensing this, or merely just in acknowledgement of the 13 years between the first movie and now, Water spends much of its first hour catching us up in a dribble of reminders. We’re on Pandora, a planet of tall blue humanoid creatures called Na’vi that Earth humans tried and failed to colonize. One of the leaders of that brigade was Colonel Miles Quaritch (Stephen Lang), who died at the end of the first movie and in this one is back as a clone (with the original guy’s memories implanted) to try to colonize once more. Here he takes the form of a Na’vi, giving him their height/speed/strength advantage as he attempts to hunt down the Na’vi once known as Jake Sully (Sam Worthington), who controlled an avatar in the first movie and eventually joined Na’vi society. His soul and avatar merged at the end of the first movie following his corporeal death, and so now he’s a full-time Na’vi (and part of a narrative tradition of male characters played by white men, like Dune’s Paul Atreides, who infiltrate a native people and end up besting them at their nativeness so as to rise to the rank of their leader). Sully has started a family with Neytiri (Zoe Saldaña), and they have several biological children as well as two adoptees: Kiri, the mysteriously birthed daughter of Sigourney Weaver’s biologist character Grace Augustine, who also died at the end of the first movie (Kiri is voiced by Weaver) and Spider (Jack Champion), a human born on Pandora who was too young to leave via cryo. Spider has retained his human form and looks like Justin Bieber if he were allowed to realize the dirtbaggiest of tendencies he was evincing a few years ago (long dreadlocks, perpetual shirtlessness, a foundation of grime on his skin constantly).

It’s all fun and bowfishing until the Earth humans come back and set more fires to the idyllic and blue-hued Pandora. Quaritch’s pursuit of Sully causes Sully and his clan to hide out amongst the “reef people” tribe of the Metkayina. These water Na’vi are slightly greener, with tails that look like the sticks of hockey goalies and thicker forearms (the better to swim with). It is here, about an hour in, that Water finally feels like something worth sitting through. The swimming scenes are gorgeous, and the film becomes a buffet of creatures that are familiar yet alien, devised ingeniously as if Cameron and his team are approaching uncanny valley as a medium unto itself. There are chiffon fish, snails whose bodies flare into wings, some dinosaur-turtle-dolphin-looking motherfuckers, and flying fish with the faces of ichthyosaurs. The pièce de résistance is the tulkun, a giant cetacean with a mouth like Dune’s sandworms—the Metkayina are particularly close to these gentle giants, rendered with the soulful eyes of their earthly whale counterparts except they have two sets of ‘em. The movie really comes to life when exploring the Na’vi/tulkun bond (one of Sully’s sons becomes very tight with an outcast).

In peak form, Water is literally wonderful, and the movie never lets you forget it. So many shots track the terrestrial Na’vi’s amazement at the oceanic sights they’re experiencing for the first time, as if Simon Franglen’s majestic score itself weren’t enough to telegraph the wonder. This is a movie that really wants you to sit back and take a load off, intellectually. Its functioning reminds me of the way a Disney park ride seems to inform its patrons: “Don’t worry, we’ll do the hallucinating for you. We got this.”

Water is ultimately a very simple, longwinded cat-and-mouse game that, whether intentionally or not, evokes so much of what came before it while managing to break new visual ground. Seeming references to Jaws 2, Cannibal Holocaust (as the white invaders burn a native village for only the sake of domination and cruelty), and Cameron’s own The Abyss abound. As it trots to its watery climax, aboard a giant capsized military ship in which several Na’vi are trapped, the movie does raise the stakes by killing off a theoretically important character—though I confess that I couldn’t tell the difference between this character and others in the immediate vicinity. Still, it does manage to be exciting when it bothers to move its fins.

There’s a lot of effort and star power here; in addition to the already named actors, Kate Winslet plays Ronal, a high-ranking Metkayina. But unless you know that going in, there’s a good chance you won’t recognize her. For all the technical achievement, which includes the first use of underwater motion capturing, this all looks like CGI, and the actors are under so many layers of animation as to be indistinguishable. I have to believe that Cameron could not get his desired effect from an entirely computer-generated world, that he needed the actors to act out their parts and learn free diving (and, in Winslet’s case, hold her breath for so long that she wondered if she had died), but I still felt like I was watching a cartoon that was divorced entirely from reality as I know it. At one point, Quaritch compliments Spider for having heart, but that seemed just as fantastical an idea as everything else in Water. It’s a movie that takes itself very seriously—its themes of the power of family are, uh, obvious and explicitly reinforced throughout—but then so do a lot of dumb, pretty things.