When Marvel first started laying the groundwork for "The Avengers" and gathering its big superheroes together, Thor always seemed like the toughest sell of bunch. Rich dude in metal suit? Sure. Genetically engineered super soldier from World War II? I’ll buy it. Norse god/other dimensional alien? Well, now we’re just getting silly, and this is in the same universe as a big, angry green guy.

So when the first "Thor" movie ended up pretty good, it was a pleasant surprise. Despite a few flaws, director Kenneth Branagh ended up being an overall inspired choice for the job, making the high royal drama work and delivering enough hammer-swinging action to please. And Hemsworth – who, as hard as it is to believe, was only known for playing Captain Kirk’s dad in the first five minutes of "Star Trek" at the time – ended up being a charismatic star in the making.

Cut to Marvel Phase Two (which never doesn’t sound nerdy) and "Thor: The Dark World," which nicely improves on the first movie’s formula and delivers a fun time fitting of the gods.

After the incident in New York, Thor returns home to Asgard to help bring harmony to the various worlds while his Earth-bound love interest Jane Foster (Natalie Portman) waits patiently, hoping to find signs of his return. She does end up finding something otherworldly, but it’s not Thor. Instead, she stumbles upon some mystical red ooze called Aether, a dangerous weapon created by Malekith (Christopher Eccleston), a Dark Elf who wants to destroy the universe.

The Aether clings itself to Jane’s body, summoning Thor … and awakening Malekith and the remains of his Dark Elf army. Thor brings Jane back home to Asgard for protection, but not long after meeting the parents (Anthony Hopkins and Rene Russo), Malekith shows up, decimating a large portion of the kingdom. Thor has a plan to fully defeat Malekith and his Dark Elves for good, but it requires the assistance of our old pal Loki (Tom Hiddleston), biding his time in Asgardian jail.

The first ten minutes or so of "Thor: The Dark World" throws a lot of exposition at the audience, getting everyone up to speed on all of the ancient wars, mystical goop, inter-dimensional portals and devious Dark Elves. It’s probably the nerdiest film Marvel’s allowed themselves to make up to this point, diving face-first into sci-fi fantasy. After you manage to survive the script’s early info-dump, the movie’s fun, adventuring spirit thankfully takes over.

Director Alan Taylor takes the reins from Branagh, and no offense to what Branagh accomplished with the first movie, but Taylor’s a significant upgrade (no more Dutch angles!). Don’t let his mostly TV-based resume ("Game of Thrones," "Mad Men") fool you; there’s nothing small screen about "Thor: The Dark World."

Taylor settles on a really nice tone that comfortably balances the fairly intense drama with the script’s consistently humorous wit. It's breezy and serious, somehow at the same time. He also has a confident eye the big-budget action a film of this size demands, capturing exciting fight scenes and some high-flying starship action that thrillingly plays like "Star Wars"-lite.

The big finale shows Taylor at his best, combining tense high stakes climactic action with hilarious insta-portal antics. It’s chaos, with characters and creatures flying back and forth between worlds. I doubt I was able to keep up with all of the switching and swapping, but it certainly was a hoot and a lot more fun than a lot of big blockbusters allow themselves.

The real reason Taylor was an inspired choice is because of his ability to build authentic worlds out of fantasy. Whereas the first film spent most of its time in New Mexico (or, to be accurate, a set vaguely resembling New Mexico), "The Dark World" calls Asgard home for most of its two-hour running time. Taylor brings just enough grounding and grit to the mystical kingdom so it doesn’t look or feel cheap

He even spreads a bit of that sense to the Earth sequences. In "Thor," being on Earth was a bit of a drag. Here, both worlds look good and feel interesting, even if the Earth sequences are mostly there for comic relief and the grand finale.

After two movies as Thor already under his belt, Hemsworth has grown into the role nicely. He’s a magnetic screen presence, easy with both humor and drama. Portman is always charming as well, and even though the role is a bit on the simpery side, she makes the most of it.

The real star, however, is Hiddleston’s delightfully sniveling Loki. The script gives him the juiciest role as Thor’s conflicted, unreliable companion, as well as some of the juiciest lines. "It’s not that I don’t like our talks," he retorts to his father during his early sentencing, "I just don’t love them." Hiddleston sinks his teeth into the role with slimy joy. He’s grown a long way as a villain, and overall as a character, since the first film.

Oh, and thank the heavenly stars, they gave Kat Dennings some funny, sharp dialogue this time through. She’s actually a solidly amusing comic relief instead of the constant facepalm she was in "Thor."

Upon a closer inspection, the story isn't exactly Mjolnir strong. In terms of depth, it’s a strange combination of a lot and a little going on at the same time, and many characters – like Thor’s band of Asgardian warriors – get left in the dust. But maybe a movie about a Norse god who slams his enemies with a spin of his gigantic hammer and Stellan Skarsgard – reprising his role as a slightly mad Dr. Selvig – running around Stonehenge in the buff isn’t exactly something that demands close inspection. Maybe it’s just meant to be an entertaining good time. And that’s exactly what it is.

Also: I don’t think I need to say this anymore, but yes, stick around through the credits.