Leading into the third Thor installment, Marvel has set off an absolute charm bomb of a marketing campaign. Trailers jam-packed with jokes promise an epic showdown between the studio's God of Thunder and the Incredible Hulk in full gladiator mode. A barrage of collectible character posters, adorable Instagram snapshots, and playful interviews across media social and mainstream brandish the visages of the film's explosively charismatic cast, which includes Chris Hemsworth, Tom Hiddleston, Mark Ruffalo, Cate Blanchett, Tessa Thompson, Idris Elba and Jeff Goldblum. And Marvel has nearly made a rock star of its eccentric and ever-playful director Taika Waititi, whose gotten everything from a fashion spotlight in major trade to a New York Times profile ahead of the release. All of this seemed to assure that Thor: Ragnarok would be one of the most fun Marvel movies yet. And it totally is. Yet, somehow, this rollicking superhero tale isn't one of the Marvel Cinematic Universe's best.

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Set about two years after Avengers: Age of Ultron, Thor: Ragnarok picks up with its titular superhero bounding about space, seeking to solve the mysterious vision that rattled him in that trippy pool. Turns out, he's seen visions of Ragnarok, the prophesied fall of Asgard. Once Loki's low-key rule leads to the rise of Hela, the Goddess of Death (Blanchett), the brothers Odinson (Hemsworth and Hiddleston) are cast out to the far corners of the universe. Specifically, they wind up on savage Sakaar, where they come face-to-face with legendary warrior Valkyrie (Thompson), zany tyrant The Grandmaster (Goldblum), and a battle-hardened and bitter Hulk (Ruffalo). From this junkyard of a planet, Thor and his scrappy new team must rally to rival Hela, and fight for the future of Asgard.

As you'd well expect from a tale of superheroes, Viking gods, beasts and gladiators, there's plenty of action to be found in Thor Ragnarok. Fueled by moody rock music and enhanced with a lavish amount of CG, these are splendid spectacle, even when computer-recreated characters get a bit overly fluid or even rubbery in their physicality. The movie boasts colorful spaceship chases, prolonged battle scenes, and fanciful flourishes of destruction, often accented by flowing capes. Naturally, there's a bonanza of fighting in the final act, where this sequel also wedges in franchise setup and requisite trailer moments. But where this film really comes alive is in its humor. After all, that's why Waititi was hired.

The New Zealand-born writer/director carved a reputation for sprouting comedy out of dark and dramatic moments with films like the coming-of-age dramedy Boy, the vampire mockumentary What We Do In The Shadows, and the wacky adventure Hunt For The Wilderpeople. So once Marvel announced Waititi would helm Thor 3, his fans predicted a fresh and funnier take on MCU's hunky God. Leaning into Hemsworth's undeniable comedic timing and goofy charm, Waititi pushes Thor to a curious and rewarding new place, where he gets to deliver the punchlines instead of setting them up, or being the butt of them.

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Throughout the film, Hemsworth positively shines. Even in the trailers, you see the fun that can be had if Thor is played as a bit more streetwise, a little less regal. This shifts some established chemistry, of course, turning Loki from the witty one to a clown, a change Hiddleston handles with a suitably biting aplomb. Thompson gets in on the fun with some physical humor and snark, while a villainous Blanchett delivers vicious bon mots, and Goldblum basically just Goldblums it up! Even a string of cameos pop up to bring in bonus hilarity. All this combines to make Thor: Ragnarok one of the MCU's funniest films, challenging The Avengers, Spider-Man: Homecoming and Guardians of The Galaxy. But there's something crucial missing from this mix that keeps it from being among Marvel's best. Sadly, the sequel repeatedly short changes its emotional beats.

Despite all its wackiness and laughs, Thor: Ragnarok is an adventure that deals in serious loss. I'll spare you major spoilers, but as the first trailer revealed this, I feel safe to say Thor loses his mighty hammer Mjölnir in act one. , a tragedy that actually comes on the heels of an even greater loss. Yet each big blow is dealt with in a pair of astonishingly terse scenes. In one, the amicable rock monster Korg (played by Waititi) declares the loss of Thor's signature weapon must feel like losing a loved one. Instead of crying or letting the gravity of that sink in, the supposedly bereaved hero just nods, and commends his new friend for summarizing this feeling so succinctly. Similarly, Banner is still reeling from the betrayal Black Widow delivered in Age of Ultron's climax. But his big moment confronting this is unceremoniously cut short, as are many other moments where a major character could face a revelation that should be of soul-shifting severity. Apparently, there's just too much plot to get through to linger on anything more than action.

Typically, Waititi is a wonder at balancing drama and humor to create complicated characters and loony yet nuanced narratives. But in working his style into the demands of the MCU, this balance is lost. It's not the jokes that detract from the drama in Thor: Ragnarok; it's that this franchise demands more plot, more characters, and much more action than the inventive director's indie efforts. To make room for all this, something must be sacrificed. Since Waititi's quirky sense of humor has played well to Marvel fans since that lovingly ludicrous short aboutThor's roommate Darryl, it wasn't going to be the jokes. Instead, the beats that would have allowed characters a moment to dwell on their loss, a moment crucial not only to them feeling the impact of it, but also for the audience to take it in, are sliced out without mercy. In their place, there's forgettable characters (chiefly Karl Urban's lackluster Skurge), requisite franchise plot points, and flourishes of fan service.

Full of action, laughs, and spirited fun, Thor: Ragnarok is a fine Marvel movie. But lacking a heaving heart, it's a disappointing Waititi offering.