As a comic mythology, the Thor sagas lack something in the same way that many argue Superman does. Like the Man of Steel, Thor has nearly boundless power, checked only by his father, and the biggest dramatic action that Thor can be involved in is losing said power and attempting to reclaim it. The inevitability of Thor’s triumphant return to glory is an albatross around the neck of Kenneth Branagh’s Thor, which at times feels less like a fully realized film and more a necessary bit of backstory in order to build to Joss Whedon’s Avengers next year.

Not that Thor isn’t quite entertaining at times. The soon-to-be-king of Asgard, the most triumphant of the Nine Realms, Thor (Chris Hemsworth) is brash and overconfident. He seeks war and conquest, lacking the wisdom of Odin (Anthony Hopkins), his father and the current king. Thor is also blind to the simmering jealousy of his brother Loki (Tom Hiddleston), who supports Thor at every turn but is beginning to grow tired of his childish bloodlust. After attempting an ill-fated coup on the kingdom of the Frost Giants, breaking an age-old truce between Odin and their king, Thor is banished to earth, and his hammer, Mjollnir, is sent there with him, until Thor proves himself worthy of its power.

Here’s where Thor takes a peculiar turn. After the CGI feast of Asgard (we’ll come back to that in a second), Thor becomes the quarry of two rivaling factions on Earth. Jane (Natalie Portman), Erik (Stellan Skarsgard) and Darcy (Kat Dennings), a team of astrophysicists, have happened upon a series of atmospheric anomalies related to the goings-on in Asgard. They happen to be at ground zero when Thor crash-lands, and take him in. They find resistance from SHIELD operatives, led by Agent Coulson (Clark Gregg, who’s found himself a handsome gig appearing in every single Marvel Studios film). Both parties are interested in both Thor and Mjollnir, especially since Erik happens to have heard tales of exactly what Thor’s talking about when he was a child.

From here, Branagh makes the curious call to establish Thor as a mixture of Shakespearean family drama and a fish-out-of-water comedy. Thor spends most of the film struggling with the loss of everything that defined him, which is to say unchecked power. The film is at its best in the exchanges between him and Jane; Hemsworth is a pitch-perfect Thor, both commanding and vulnerable, and Portman for her part plays the romantic lead for as much as one can really get out of such a role. They also seem to be keyed into the wit of the film more than some of the other actors, with Hemsworth in particular channeling Chris Pine’s work as Captain Kirk in the Star Trek reboot and lending Thor a cocky smirk that drives home a lot of the overcooked jokes with more conviction than they really deserve.

The big issue with Thor is that the two halves of the story feel completely incongruous. This is partly due to the fact that while Branagh has a certain flair for popcorn action filmmaking and gets uniformly good-to-great work out of his actors, CGI is very clearly not his calling. The action is done well, but it’s very (very) clearly happening outside any sort of realistic spatial area. For a film as big-ticket as this one, most of the dialogue exchanges in Asgard are blatantly done in front of a green screen, which takes the wind out of the sails of some very good moments, particularly the climactic showdown between Thor and Loki, which Hemsworth and Hiddleston sell the hell out of only to be undercut by the blurry, backdropped action. While it’s clear that Branagh was aiming for a surreally beautiful, fantasy-rich land, Asgard instead just looks silly and unconvincing.

This is especially upsetting in the final hour, when the film really kicks into overdrive and begins to exceed expectations. The oddity of Thor is that, upon its ending, you almost hope Branagh gets another go. There’s good here, and this could evolve into a capable dark horse franchise with Hemsworth at the helm. It’s not there yet, though, and as it stands, Thor will likely be remembered the most as one of the bridges to The Avengers. As always, with the Marvel Studios films, make sure you stick around past the end credits, for a big hint (and a potentially upsetting one) as to the direction that next year’s installment will take. It’s just a shame that such things overshadow Thor itself.

(A final note: The action was blurry and at times incoherent in 2D. I can only imagine what it looked like in post-production 3D. Leave a comment if you’ve seen it in that medium.)