"Thor" was half of a very good superhero movie.

Thrust into a civilization of Earthlings he couldn’t quite comprehend, Chris Hemsworth’s swaggering Asgardian made for some delightful god-of-thunder-out-of-water moments.

But the stuff on Asgard and Jotunheim? Hoo boy! The Frost Giants seemed better-suited to one of those Rankin/Bass animated holiday specials. And the Rainbow Bridge felt like something that would have connected the Care Bears to the My Little Ponies.

Rather than playing to the original’s strengths, though, "Thor: The Dark World" doubles down on Asgard, while introducing the realms of Vanaheim and Svartalfheim. With its dark elves, some kind of lava beast known as the Kurse, and too much time spent walking around in cloaks, the sequel too often feels like watered-down Tolkien.

As we’re told a couple of times in "Thor: The Clumsy Exposition," the dark elf leader Malekith (Christopher Eccleston) threatened to plunge the Nine Realms into eternal darkness until he was robbed of his secret weapon, the Aether. Too powerful to be destroyed, the Aether was buried "deep somewhere where no one will ever find it." Imagine everyone’s surprise, then, when astrophysicist Jane Foster (Natalie Portman, radiant as ever) stumbles across it in an abandoned London building.

After encountering some sort of extraterrestrial wooly boogers, Jane is infected with the Aether, summoning Thor to whisk her away to Asgard for a cure and awakening a hibernating Malekith in the process. As "Thor: We Get It Already" over-explains, it’s almost time for the convergence, that period every 5,000 years when the Nine Realms align and everything goes wonky, making it the perfect time for Malekith to inflict the most damage, assuming he can get the Aether out of Jane.

All this is mostly just an excuse for Thor to have to turn to his imprisoned, mischievous little brother, Loki (Tom Hiddleston), for help. Fan favorite Hiddleston has a grand old time in "Thor: Yay! Now You Can Root for Loki." The action gets back to Earth just often enough for Hemsworth to be amusingly out of place. And Chris O’Dowd underplays a couple of fun scenes as a potential rebound for Jane, because, you know, Thor didn’t even bother to call while he was battling the Chitauri in Manhattan during "The Avengers."

Most of the other attempts at humor fall flat in "Thor: We Have No Idea What to Do With Kat Dennings, But People Liked Her the First Time So We’re Gonna Try." Jane’s grating intern, Darcy (Dennings), has "hired" her own intern (Jonathan Howard) for some forced shenanigans. And Dr. Erik Selvig (Stellan Skarsgard) mostly just runs around in various states of undress. But you’re likely to find yourself wishing for more of them, just so the focus will return to a world you’re invested in.

Odin (Anthony Hopkins) returns to give Thor someone to argue with. Frigga (Rene Russo) gets to showcase her kick-ass side. Heimdall (Idris Elba) still looks like an extra from "Flash Gordon." And Lady Sif (Jaimie Alexander) and the Warriors Three are mostly sidelined, even after an unrecognizable Zachary Levi was hired to take over as Fandral, aka the Robin Hood-looking one.

Alan Taylor, who’s directed a half dozen episodes of "Game of Thrones," is a good fit for the fantasy aspects of "Thor: The Big Tent for Fanboys of Every Genre." And screenwriters Christopher Yost, known for his work on several Marvel animated series, and the team of Christopher Markus and Stephen McFeely (the "Captain America" movies) clearly know their source material.

But there’s a glaring hole that likely will affect every post-"Avengers" solo outing. Malekith and his spaceships invade London, threatening to destroy the planet, yet no one lifts a finger to help Thor and his ragtag band of scientists. Sure, Robert Downey Jr. is too expensive. And Clark Gregg’s Agent Coulson is currently mired in the diminishing returns of "Marvel’s Agents of S.H.I.E.L.D." But no one thinks it’s odd that, say, Black Widow, Hawkeye or Nick Fury don’t lend a hand.

Hiddleston’s Loki is slowly growing on me. And I’ll show up anytime Hemsworth decides it’s hammer time. Even if, like "Thor: The Missed Opportunity," the story isn’t worthy (Hemsworthy?) of his talents.

Hopefully for his next outing, Marvel will ditch the CGI-ed realms and focus on a more relatable story. But with Alfheim, Niflheim and Muspelheim still unexplored, I’m not holding my breath.