When Disney conducted its grand experiment in rebuilding the Muppet brand name in 2011 with The Muppets, the results were inconclusive: pleasingly off-kilter and nostalgic, but in the most punishingly authoritarian way possible. Nostalgia was, at a certain point, the only driving element of the plot and the only thing to get back out of it.

So in some regards, the new Muppets Most Wanted is a step in the right direction: it is actually a thing that exists mostly in reference to itself, and not as a feature-length exercise in wish fulfillment on the part of its co-writer and top-billed actor. It's not even as blunt a remake of The Great Muppet Caper as much about the plot seems to promise, including some extremely specific details of structure. And at the same time, Muppets Most Wanted feels like a mighty, determined act of wheel-spinning: there's a profound sense of fatigue and non-creativity that overwhelms the movie and leaves its handful of undeniable top-shelf moments (nearly all of them involving musical numbers) feeling like a chain of lonely islands.

The film's best moment, at any rate, is the one that opens it: in the immediate aftermath of The Muppets, as the camera stops rolling everyone looks to Kermit the Frog (Steve Whitmire) to decide what to do now that the franchise has been reborn. This triggers a rollicking musical number, "We're Doing a Sequel", that has more than a little of Great Muppet Caper's "Hey, a Movie!" opening song in its DNA, and is the one place in the entire film where the guileless postmodernism of the Muppets at their best pokes through with something of the "Let's put on a show" attitude of the best of the earlier movies and The Muppet Show itself.

From here on, the film descends into an adventure-movie rhythm that's never draggy or dull, but is also frequently no more than wistfully amusing. Short version: the Muppets are encouraged by obvious conman Dominic Badguy (Ricky Gervais) - pronounced "badji", he insists - to go on a European tour to make the most of their newly regained fame; this is merely a pretext to allow international thief Constantine (Matt Vogel), a dead ringer for Kermit but for his mole, to swap places with the frog showman, and for he and Dominic to use the Muppets' appearances as covers to rob local museums of their treasures, all clues that will aid in a heist to steal the Crown Jewels from the Tower of London.

That offers plenty of room for genial culture-shock comedy, with knowing caricatures of several Western European cultures drifting across the film's bow as it goes along, and I will happily admit to being hugely grateful after The Muppets for there to be a Muppet movie in which the actual Muppets are the main characters, with the flesh-and-blood humans (the usual constellation of cameos, with Ty Burrell and Tina Fey joining Gervais as the featured people) serving strictly in supporting roles. And without the heavy weight of reintroducing the characters, they get a good chance to breathe and express themselves in this new scenario - Whitmire's Kermit has certainly never been better, as the performer finally frees himself up to express some frustration and desperation that feel totally in-character for the iconic frog, and yet also like emotional places that Jim Henson would probably not have taken the character.

A little bit of pleasantly low-key comedy goes quite a long way, though. And as the film moves on, relying on the same small range of gags (the Muppet gang is all a bit short-sighted and unobservant! songs that are parodies of other song forms! the French have incredibly generous labor standards compared to the United States!), it gets sleepier and sleepier, feeling less and less creative. Without having any reason whatsoever to suppose that this is true, I can't help but feel like this is not a script that was filmed because the creators felt passionate about the opportunities it presented, but because a new film had to be made, and when it was time to commit, this was the material they had. It lacks inspiration, and even more, it lacks the squishy, profoundly sincere sentiment and love of humanity that animates all of the best stuff made during Henson's life, and in brief moments since his death. When Muppets Most Wanted starts to pivot to lessons about want vs. need, and the bonds of friendship and family, it doesn't feel like the heart of the movie bleeding through the comedy, but like kiddie movie boilerplate.

Also, the film puts a lot of emphasis on Walter (Peter Linz), the new human Muppet introduced as one of the main characters in the last film, and it's becoming increasingly clear that he's just no damn interesting. No slight to Linz; not even to writers James Bobin & Nicholas Stoller, whose attempt to turn the little beige man's simplicity in something charming and positive. But bland human Muppets just aren't that appealing.

Anyway, all this being disappointingly true, Muppets Most Wanted still offers plenty in the way of charming, light humor - those song parodies, however one-note the gag starts to feel, tend to be awfully good - and the breezy way that the plot is blitzed through in quick dialogue and short scenes keeps things moving without sacrificing the stakes. Bobin, who also directs, has learned quite a lot in the intervening years: the compositions favor the Muppets this time in a way that they didn't (and given the human focus, often couldn't) in the 2011 film. He and his crew - these are massively complicated films, it doesn't do to pretend like shots are set-up on the fly - also manage the feat of putting Muppet and humans in the same frame, without letting it feel like there's far too much headspace (a savvy combination of wide shots and unobtrusive high angles; there's also some smart use of deep compositions, especially during Kermit's sojourn in a Siberian prison). All of this contributes quite a lot to the sense that the Muppets are the focus and the stars, and their reality is quietly insisted-upon in a way that hasn't been achieved since Henson's death, really. This is, I want to be entirely clear, a Very Good Thing. The technical and to a large degree the performative aspect of the Muppets have been entirely re-learned and perfected (I remain vaguely unenthusiatic about all of Eric Jacobson's versions of Frank Oz's old characters). If they can nail the script next time, then we'll have some actual Muppets on our hands, and not these fan-fiction Muppet analogues who go through the motions well, but really just don't have the wit or the heart.