For DC's movie universe, Aquaman might've been sink or swim.

Happily, after Wonder Woman lifted DC out of the doom and gloom of the Batman and Superman movies, Aquaman heaves into view with another splashy success. It's a huge hit with critics and it's already been a massive hit in China.

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The movie, in theaters worldwide now, is an enormously entertaining slice of oceanic epicness, combining a seafaring sense of humor, spectacular visuals and Game of Thrones-style dynastic fantasy.

Jason Momoa is Arthur Curry, a hulking man-mountain who both drinks like a fish, and talks to them. The story opens with his Atlantean mother, Nicole Kidman, fleeing an arranged marriage by falling in love with literally the first man she sees. Arthur is the result, growing up on dry land. The obligatory school bullies awaken his powers, but the fully grown Aquaman would rather be propping up a bar than knocking down bad guys.

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Unfortunately, his half-brother decides to unite the denizens of the ocean for a war against the surface people, and Arthur has to put down his drink long enough to follow a treasure map and prevent all-out war. What follows is great fun, as Momoa's over-the-shoulder smolder and amiable jokes lighten the endless arguments about submarine sovereignty.

In the hands of director James Wan, Aquaman is gleefully inventive visually, filled with swooping long-take fights and sumptuous seascapes. The underwater world of Atlantis is a beautifully realized fantasy realm complete with different places and tribes, giving the film a genuine depth.

Enlarge Image Warner Bros. Pictures

Highlights include a flare-lit dive through a shoal of fanged sea beasts, a truly epic final battle and a swashbuckling chase across sun-dappled Mediterranean rooftops and piazzas. Despite the acrobatic camerawork and impossible stunts, this sunlit island fight sequence has a physical, real feel that this kind of CG-indebted action scene often lacks. In fact, the effects-driven sequence feels more convincing than the scenes at Arthur's home, which manage to make two people standing next to a lighthouse look less convincing than an undersea kingdom full of cross crustaceans.

The seafaring silliness is anchored by great casting and watertight performances.

Patrick Wilson is magnetic as Aryan Atlantean King Orm, who can't get over Arthur being mixed race. Alongside him, we're treated to the ludicrously enjoyable sight of Dolph Lundgren and Willem Dafoe being very serious about matters of royal succession while bobbing about on giant neon seahorses. These priceless bits of casting in such unashamedly comic-inspired capers reminded me of the 1980 camp classic Flash Gordon and its primary-colored royal romping.

Enlarge Image Warner Bros. Pictures

If anything, Aquaman himself feels like he's swimming in the slipstream of the other characters. Orm's scheming drives the plot, while another villain gets the cool suiting-up montage usually reserved for the hero. Amber Heard's resourceful and determined Mera is the one pushing Aquaman on their quest, and Momoa's laid-back hang-10 geniality means the film doesn't sell Aquaman's supposed ocean flaw. Aquaman is so laid-back, it actually feels a bit weird in the final showdown that the women characters suddenly become bystanders when there's little to stop them taking charge.

As much fun as it is, Aquaman really doesn't need to be two and half hours long. It repeats itself -- count the number of times people are talking when a wall explodes next to them -- and comes dangerously close to borrowing from other very recent superhero movies. It's clearly inadvertent, but the royal tribalism is pretty close to Black Panther, while Nicole Kidman as the hero's mother feels very close to Michelle Pfeiffer as the mother in Ant-Man and the Wasp.

Still, this is unexpectedly giddy, fishy fun. Aquaman arrives in theaters alongside Bumblebee and Spider-Man: Into the Spider-Verse, making this a good month for charming and compelling family blockbusters. Come on in, the water's fine.

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