Producers: Rob Cowan, Peter Safran and James Wan   Director: James Wan   Screenplay: David Leslie Johnson-McGoldrick   Cast: Jason Momoa, Patrick Wilson, Amber Heard, Yahya Abdul-Mateen II, Nicole Kidman, Randall Park, Temuera Morrison, Dolph Lundgren, Martin Short, Jani Zhao, Indya Moore, Pilou Asbæk, John Rhys-Davies and Vincent Regan   Distributor: Warner Bros.

Grade: C

James Wan’s first “Aquaman” movie, from five years ago, was an agreeably comic-booky lark, whose unusual visuals and winning sense of humor made it a better-than-average superhero flick, easily one of the more agreeable installments in the uncommonly dark DC Universe series.  His sequel, “Aquaman and the Lost Kingdom,” reassembles many of the elements of its predecessor, but as a whole falls considerably short of it.  It’s still pretty captivating from a visual standpoint—the addition of 3-D is unobjectionable even if it adds little of consequence—but is weighed down by a prosaic narrative and a strained sense of fun, as well as a performance by Jason Momoa in heroic mode as heavy-handed as his villainous turn was in “Fast X.”

The movie begins with a prologue reminding viewers of what happened in the first picture, and then picks up a year or so later.  Arthur Curry, aka Aquaman, the half-human, half-Atlantean he-man, is now King of Atlantis, but it’s a role he doesn’t relish, since it requires him trying to convince a quarrelsome council of elders to undertake policies—like making contact with the surface world—they find unpalatable.  No wonder he spends most of his time still living with his human father Tom (Temuera Morrison), the lighthouse keeper, taking care of his son, infant Arthur Jr. (played by a variety of kids).  His wife Queen Mera (Amber Heard) seems to spend more time in Atlantis, where she keeps track of the ongoing political machinations, as does Aqua’s mother, the Dowager Queen Atlanna (Nicole Kidman).

And trouble is certainly brewing.  David Kane (Yahya Abdul-Mateen II), who blames Aquaman for the death of his father and has vowed to take revenge, employs the researches of marine scientist Dr. Shin (Randall Park) in an effort to locate Atlantis to destroy it.  Their efforts take them to tunnels beneath the Arctic, where Kane finds a powerful black trident that brings him a vision of a hideous figure, Kordax (Pilou Asbæk in CGI mode), who promises to guide him in its use.  It’s eventually revealed that the evil Kordax was the king of the lost realm of Necrus, who vied with his brother Atlan (Vincent Regan), the king of Atlantis, for rule but was defeated and imprisoned in an icy tomb.  He schools David, who becomes Black Manta when he puts on a special helmet, in the use of ancient technology fueled by an element called orichalcum, which the Atlanteans had buried in secret vaults after learning that it nearly destroyed the planet because of its extraordinarily high emission of greenhouse gasses. 

David’s extraction of orichalcum from the vaults, and his use of it to regenerate ancient weaponry, leads to a spike in temperatures that could end earth’s existence.  When he and his henchwoman Stingray (Jani Zhao) attack Atlantis and injure Mera in the process, Aquaman recognizes that he cannot face his nemesis alone, and decides to free his half-brother Orm (Patrick Wilson), who had fought him for the throne, from the prison of The Fishermen, a kingdom in the Atlantean federation, where he is being held.  He travels to the pirate demimonde presided over by Kingfish (a CGI figure voiced by Martin Short) to learn Orm’s location, and then extracts him.

Much of the rest of the movie consists of the constantly sniping brothers working together, though none too smoothly, as they travel through strange and dangerous places, some infested by huge plants and insects mutated by the orichalcum radiation, to find Black Manta and his crew and the location of Necrus.  They’re aided by King Nereus of Xebel, Mera’s father, and the oversized, literally crabby Brine King (a CGI figure voiced by John Rhys-Davies) and, at one important point, by hordes of whales summoned by Aquaman, whose songs counteract the effect of Manta’s sonic cannon.  They also get assistance from Shin, who never agreed with Kane’s nefarious plans.  (Seriously, do you think that Park could ever play a real villain?)

The plot takes a rather ugly turn in the last act, when Manta learns that Atlan created the seal keeping his brother imprisoned with blood magic, and that the blood of one of his descendants can break it; so he kidnaps Arthur Jr. with the intent of sacrificing the infant.  Aquaman and Orm arrive in time to prevent that, of course, but the confrontation with Manta and, eventually, with the unleashed Kordax himself goes back and forth before the half-brothers emerge victorious.  In an epilogue Aquaman convinces his council that they must work with the surface dwellers to combat climate change (you knew that was coming, didn’t you?)

Wan and his screenwriter David Leslie Johnson-McGoldrick know their genre movies and happily crib from them—Kingfish is clearly a thinner Jabba the Hutt, and he’s serenaded by a band that might have swooped in from the “Star Wars” cantina; and on his foray to free Orm Aquaman is accompanied by a cute, intelligent CGI octopus that that’s like a mollusk version of R2D2.  There are jokes here as well, but not as many as in the first movie, and pretty puerile.  Arthur spends much of his first scene getting sprayed by his son’s projectile urination, for instance, and introduces Orm to human food by suggesting that he eat a live cockroach (the makers think that bit, a gag in every sense, so good that they repeat it in the closing credits).  The barrage of bickering between the two brothers contains no gems, either, though at one point it sounded as though Aquaman called Orm “Loki.”

Most of the performances are pretty perfunctory, though as noted Momoa hams it up badly, while Wilson balances things out by being stoic and imperturbable.  Abdul-Mateen, surprisingly, is boringly impassive, but Park lends some comedy relief.  Everyone else goes through the motions; the CGI figures are generally more engaging than the human ones.  Though it lacks the glistening, shimmering surfaces of the first film, the technical work here—by production designers Bill Brzeski and Sahby Mehalla, costumer Richard Sale, cinematographer Don Burgess and the huge effects contingent—is solid, though as usual the 3-D format darkens the images.  Editor Kirk M. Mori does a reasonably decent job of ensuring that the elaborate exposition material, as ridiculous as it might be, remains reasonably clear, and though Rupert Gregson-Williams’ score is as bombastic as you’d expect, the sound mix tones it down so that it doesn’t obliterate the dialogue, as banal as it might be.

Back in 2018, “Aquaman” was part of a franchise—the DC Universe—that was still thought to be viable. Since then, or course, the series has been shelved to make way for a reboot, and this movie has become its final installment.  It doesn’t exactly close out the DCU with a whimper, but it doesn’t end it with a bang, either.