[Hollywood Grind is a new weekly column that explores the intersection where US movie studios and common sense collide.]

How much do you need to know about Thor? If you said, "Not a lot -- he's a Norse god come to Earth, right?," then you're in for an interminable first 30 minutes of the movie bearing his name.

Directed by Kenneth Branagh with all the anonymity you'd expect from a direct to video sequel, Thor starts promisingly in the New Mexico desert as a storm approaches and a trio of humans run into the titular character, played by Chris Hemsworth with a proper dose of confident swagger. Then we flash back to an origin story and that's where the film bogs down completely.

In this day and age, do we need origin stories? In the past, TV shows could set up their entire premise over the opening credits with a song. (Hello "The Brady Bunch"! Hello "The Jeffersons"!) Somehow, though, the makers of superhero movies (and the studios that back them) have gotten the idea into their heads that origin stories are a must, as though every generation requires -- or deserves -- their own.

Set-ups are a necessary evil, but Thor handles its set-up clumsily by flinging the story back to a fantasy CGI world that's indistinguishable from any other fantasy CGI world, with huge crowds of pixels inhabiting palaces of pixels. It's beautiful in an incredibly cold fashion, like Tron: Legacy with a busier color scheme.

The fantasy CGI world is called Asgard, one of the Nine Realms, and it is ruled by wise old Odin (Anthony Hopkins). His wife (Rene Russo) doesn't say much. His sons Thor and Loki (Tom Hiddleston) each want to be king, but Thor is Odin's choice. Just before Odin can make the official pronouncement, however, Asgard is invaded by Frost Giants, creatures from Another Realm who once wrecked havoc on Earth (which is known as Midgard, and/or Still Another Realm). Thor feels that the realm of the Frost Giants must be invaded and fear instilled to prevent future attacks. Odin tries to calm him down to avoid war, expressly forbidding him to stir up any trouble, but Thor feels that action must be taken.

Don't worry about spoilers: what I've described in the paragraph above is only about the first 15 minutes of the movie. There's still an extended CGI battle, more kingly pronouncements, and severe consequences to be paid before the movie returns to Earth.

None of that is actually needed for the story to proceed. It's there to provide a meatier role for the actor who plays Odin, it's there to feature a CGI action sequence, it's there to show off the splendors of Asgard, it's there as an excuse for why the movie is presented in 3D and therefore demands a higher price be paid for every ticket sold for said 3D screenings.

The movie stops, in other words, before it even begins, so that we can pay attention to the origin of a character in whom we have no interest.

Granted, once the movie begins, it's a fun little "Norse god out of heaven" story, with Kat Dennings providing capable comic relief, Stellan Skarsgård expressing concern, and Natalie Portman picking up a nice paycheck. Other good, interesting actors (Idris Elba, Ray Stevenson, Tadanobu Asano, Jaimie Alexander) pop up in small supporting roles, adding human vim and vigor to the computerized spectacle.

It's all rather ... OK. I didn't actively hate the movie, but the extended opening definitely wore down my patience. (Others, such as my esteemed Twitch colleagues Scott Weinberg and James Marsh, enjoyed the movie quite a bit more than I did.) And we have more superhero origins coming this summer, what with The Green Lantern and Captain America: The First Avenger, plus a new Superman threatening to bludgeon us to death with needless dwelling on beginnings.

Maybe it's just that my tolerance for detailed origin stories has evaporated over the past decade of super-serious superhero explications. The original Star Wars had the right idea: throw all that crap into an opening crawl. Let's get on to the story with as much dispatch as possible, shall we? Or is that too much to ask?