The creators of the new Masters of the Universe movie really, really, want to let you know that they’re in on the joke. They know deep down, or at least they should know, that their juvenile material is only suitable for children or overgrown adolescents with a terminal case of childhood nostalgia. So director Travis Knight (Bumblebee, Kubo and the Two Strings) and his quartet of screenwriters have loaded the proceedings with so much campy, self-referential humor that you don’t know whether to laugh or cry. The film winds up feeling so much like one of those fringe festival musical theater parodies that you find yourself waiting for the characters to burst into song.

All of this might go over well with the fanbase who grew up playing with the Mattel toys and subsequently immersed themselves in the myriad product spin-offs, including comic books and an animated television series, that followed in their wake. The packed house at the preview screening, greeted with swag including free tote bags and action figures, certainly roared with approval, especially at the film’s myriad Easter eggs, cameos, etc. But it’s hard to imagine viewers not already immersed in the Universe finding this an engaging entry point.

Nicholas Galitzine (The Idea of You), undergoing the familiar ritual of promising young actors bulking themselves up for a franchise movie role, works hard — too hard — to infuse his characterization with endearingly goofy humor. After an opening sequence in which a young Prince Adam (Artie Wilkinson Hunt) sees his beloved planet Eternia conquered by the evil Skeletor (Jared Leto) and his minions, we encounter him as an earthling stuck in a human resources job and scaring off dates with his stories of hoping to reunite with his royal parents if he could only find his Sword of Power.

Spoiler alert, he does find the sword in, where else, a sci-fi collectible store. After being attacked by a grotesque creature, he’s reunited with his childhood friend Teela (Camila Mendes, Riverdale), now a grown-up badass who whisks him back to Eternia. Unfortunately, things aren’t going so well there, with Skeletor and the witch Evil-Lyn (Alison Brie, auditioning to play Cruella de Vil in the next reboot of 101 Dalmatians) in charge and Teela’s warrior father Duncan (Idris Elba) now a drunken wreck.

It takes a while, seemingly forever, for Clark Kent, I mean Prince Adam, to fully access the power of his sword by uttering that magic phrase “By the power of Grayskull!” and transform into He-Man, shedding his nerdy clothes for a loincloth while the camera lingers lovingly over his abs. Cue the resulting epic battles as He-Man — along with such allies as Fisto (Jóhannes Haukur Jóhannesson), Ram Man (Jon Xue Zhang) and Mekaneck (James Wilkinson) — battle Skeletor and his forces for control of Eternia.

Joining in the fray are such beloved characters as the wisecracking Roboto (voiced by Kristen Wiig) and He-Man’s green-striped tiger, who has a bit of a cowardly streak. “Next time I’m definitely wearing armor,” the tiger announces just before going into battle. The Sorceress (Morena Baccarin) pops up during particularly tense moments to offer magical support.

There’s more, lots more, with the film seemingly incorporating every character that’s ever been part of the series, whether to please longtime fans or make sure that the toy store shelves are fully stocked for Christmas.

On one hand, it’s admirable that the film doesn’t take itself too seriously. But the relentless jokiness might have worked better if the material were actually funny. From the moment it begins with Prince Adam’s hokey, self-mocking narration, the jokes are so lame they become cringeworthy. There’s a running gag about Adam’s roommate secretly watching tearjerker movies and hiding his tears when Adam shows up that feels like something left over from an ‘80s sitcom. And when Adam tries to prove his real identity to various disbelievers on his home planet, he shows them his driver’s license.

The dialogue is even worse. “Why would he do this?” Adam asks Teela forlornly when he first sees the planetary destruction Skeletor has wreaked. “Because he’s bad,” she replies. Well, duh. During one violent battle, a character exclaims “We’re saved!” only to change it to “We’re screwed!” a second later.

Attempting to rally the troops, He-Man shouts at the macho Fisto, “How much do you bench?”

“What is bench?” Fisto confusedly replies.

And in a climactic face-off with Skeletor, He-Man tries to reason with the villain who has a skull for a head. “Maybe you weren’t loved enough as a child,” he gently suggests.

In between the bits of Borscht Belt humor there are plenty of action sequences, staged by Knight in the frenetic fashion typical of comic book movies and accompanied by Daniel Pemberton’s bombastic score featuring squealing doses of rock guitar courtesy of Brian May. But the kinetic mayhem feels more dutiful than exhilarating, with nothing really seeming at stake.

The performers appear to be enjoying themselves as they go through their silly paces, although it’s too easy to imagine them cracking up whenever the director yelled “Cut.” Leto, adopting a vague British accent, provides some amusing moments as Skeletor. Assuming that is Leto, of course, since his voice is disguised and we never see his features. Nice work if you can get it.

Masters of the Universe touches all the fan-serving bases, with a fun cameo by a certain star of a previous film incarnation and enough post-credit sequences to guarantee several sequels. But it all comes off as terribly forced, as if everyone involved was already trying to figure out exactly how much they’ll earn signing autographs at future Comic-Cons.