- - Thursday, May 5, 2011

“Thor” opens on a starry night in the New Mexico desert. Two scientists - Jane Foster (Natalie Portman) and Erik Selvig (Stellan Skarsgard) - and their assistant, Darcy (Kat Dennings), are out hunting for evidence of a rare cosmic phenomenon they think could provide a bridge to another dimension.

Before long, they spot what they’re looking for - a gargantuan light storm flaring up in the midnight sky. Selvig, shocked by its size, turns to Foster, saying, “I thought you said it was a subtle aurora.” Not a chance. There’s nothing subtle about “Thor,” an expensively produced, effects-heavy superhero film presented in 3-D that frequently resembles a sort of oversized light show itself. There may not be a lot to it, but it’s bright, flashy and plenty of fun to watch.

Like several other major films this summer, “Thor” is a comic book movie. It’s based on a hammer-swinging Marvel Comics hero who first appeared in 1962. As with many of its Marvel-inspired cinematic predecessors - “Spider-Man,” “Iron Man,” “The Hulk,” and “X-Men” - it’s been given a thoroughly modern makeover, ditching the comic’s clunky god-brought-to-Earth trappings in favor of a tale about a young hero discovering his own identity and finding his place in the world.

The difference this time around is that Thor’s world is not our own. As a flashback and voice-over (strongly reminiscent of the first “Lord of the Rings” film) handily explains, after fading from popularity, the Norse gods of old returned to the mythical realm of Asgard. There, the one-time god Thor (Chris Hemsworth) is a powerful prince set to assume the throne from his king and father, Odin (Anthony Hopkins).

But transferring power is easier said than done. In the midst of the coronation ceremony, Asgard’s old enemies, the Frost Giants, sneak into the city and attack. Could Thor’s scheming younger brother, Loki (Tom Hiddleston), have had something to do with it? If you’re not sure, you’ve probably never seen a summer blockbuster before. With a convoluted story designed to provide maximum visual stimulation and set up next summer’s “Avengers” film (which will feature Thor alongside other Marvel characters), “Thor” offers little in the way of narrative surprise. The scattered script, by Ashley Edward Miller, Zack Stentz and Don Payne, is little more than a 3-D thrill-delivery machine.

Yet director Kenneth Branagh, best known for his big-screen Shakespeare adaptations, invests the film with a glorious sense of myth and majesty anyway. Much credit, of course, is also a credit to the artists and effects wizards behind Asgard, a sparkling, floating urban landscape that resembles the Emerald City by way of Frank Gehry.

The effects aren’t all that’s easy on the eyes. Miss Portman, as a perky, pretty-eyed astrophysicist, gives a perfect portrayal of an innocent geek girl caught up in an unexpected adventure. (“Thor” is the rare summer superhero film that features a young woman as the primary audience stand-in.)

As the muscle-bound, golden-maned hero-god, Mr. Hemsworth exudes a strength and confidence that somehow manages to mask the essential shallowness of the character. It’s a breakout role for the young actor, and those who enjoy his presence will probably enjoy the rest of the movie as well. No one would mistake it for subtle, but despite its lack of depth, it’s big and winning and plenty easy to enjoy.

TITLE: “Thor”

CREDITS: Directed by Kenneth Branagh; screenplay by Ashley Edward Miller, Zack Stentz and Don Payne.

RATING: PG-13 for nonstop 3-D fantasy violence

RUNNING TIME: 114 minutes