“Aquaman”
***
(PG-13, 2:23)

You have to give credit to James Wan that “Aquaman” is as good as it is. The “Saw” and “The Conjuring” filmmaker doesn’t do anything halfway. He took a character from the hit-or-miss DC Comics Extended Universe, best known from the HBO show “Entourage” and a brief “Justice League” appearance, and made the biggest, goofiest, craziest aquatic superhero action movie he could.

“Aquaman” is pure camp, wildly entertaining and an eye-popping spectacle. You have to admire the effort, scope and sheer audacity of everyone involved — especially Wan, who throws it all at the screen. To his credit, most of it sticks, if you’re willing to dive right into this wacky ocean adventure.

Nicole Kidman sets the tone for this bombastic and kooky movie, playing a quirky mermaid Barbie who washes ashore and is rescued by a kindly lighthouse keeper, Tom (Temuera Morrison). She’s Queen Atlanna of the underwater kingdom Atlantis. The fruit of their union is the hunky, long-haired Arthur (Jason Momoa), half-human, half-Atlantean and bestowed with his mother’s unique oceangoing gifts — underwater breathing, super-strength, extremely good fighting skills — which he applies to taking down high-tech pirates, clad only in jeans and tattoos.

Wan assembled quite the esteemed cast to support Momoa and populate the fantastical undersea world, including Willem Dafoe, Dolph Lundgren, Amber Heard and frequent collaborator Patrick Wilson. What’s most impressive is just how committed the actors are to the completely silly affair, clad in shimmering wetsuits, astride giant seahorses and hammerhead sharks. As King Orm, Wilson bellows about his plan to become the “Ocean Master” with a Shakespearean intonation that contrasts nicely with his half-brother Arthur’s relaxed surfer-brah demeanor.

The plot is a globe-trotting, seafaring scavenger hunt to track down King Atlan’s trident so Arthur can challenge the war-mongering Orm’s claim to the throne of Atlantis. It’s a zany journey, as Princess Mera (Heard) and Arthur travel to the various ancient Atlantean kingdoms by sea and land for clues. They stop off in the Sahara and in Sicily, while fighting off the stormtrooper-esque commandos sent to kill them by Orm, as well as the vengeful, laser-eyed supervillain Black Manta (Yahya Abdul-Mateen II).

This is the kind of movie where Mera will inexplicably play a flute, and Arthur frequently loses his shirt for no reason at all. But why question it? A giant octopus pounds war drums — heck yeah. It’s funny, intentionally, and at times, immaturely so. But Wan’s enthusiasm is infectious, his effort exhaustive. The Lovecraftian aesthetic is bold and intoxicating, the tone light and the references deep.

One hallucinatory neon chase scene set to a thumping electro beat is straight out of “Tron: Legacy,” while another dark, gothic journey into a deep-sea trench filled with savage, snapping monsters taps into Wan’s horror background. The bouncy chemistry between Arthur and Mera is pure screwball comedy, drawing from “It Happened One Night,” while the fantastic setting likens it to “Valerian and the City of a Thousand Planets.” Then there’s the battle against a bellowing crab, the King of the Brine, that is straight out of Tolkien.

“Aquaman” is an overstuffed two-and-a-half-hour behemoth, and though it skimps on things like character development, there’s enough to distract from that. Wan and screenwriters David Leslie Johnson-McGoldrick, Will Beall and Geoff Johns know this movie is for kids and for those who want to feel like kids at the movies, and this visual extravaganza delivers just that. So come on in, the water’s fine.