Once upon a time, comic-book movies used to be camp, riding the line between silliness and sincerity that would suit the cinematic adaptation of a slim, illustrated story about superheroes and their exploits. But around 20 years ago, the superhero industrial complex rejected camp, becoming dark and gritty, then sarcastic and flip, then cycling back to wholesomely earnest again for a time. However, in today’s moment of waning superhero enthusiasm with audience fatigue setting in, it seems there’s an opening for comic-book movies to be stupid again — stupidly fun, especially if “Madame Web” can tell their fortunes.

To get a little pretentious about this latest ultra-silly Sony Marvel movie, Susan Sontag would have loved “Madame Web.” Or maybe she would have found it offensive, but either way, it perfectly fits the rubric Sontag lays out in her famed 1964 essay “Notes on ‘Camp,’” because, to borrow her phrase, “Madame Web” is a comic-book movie “in quotation marks.”

It is also the purest form of camp in that it is unintentionally so; certainly director and co-writer S.J. Clarkson, the maker of dozens of television episodes, including the two Marvel series “Jessica Jones” and “The Defenders,” didn’t intend for “Madame Web” to be as ridiculous as it is. Two of the credited writers (there are at least four) are Matt Sazama and Burk Sharpless, who also co-scripted the last baffling Sony Marvel movie, “Morbius,” which was meme’d into infamy in 2022. They’re responsible for the film’s campiness, in that the dialogue on display here is laughably cumbersome and unnatural.

But the most important element of the camp on display in “Madame Web” is the madame herself, Dakota Johnson, who has a preternatural ability to apply quotation marks to a line reading with the combination of her guileless blue eyes and a smirk on her lips, a skill she deploys to viral fame during almost every press appearance. It is a performance akin to Michelle Williams’ turn in 2018’s “Venom” (yet another silly/fun Sony Marvel flick), in which the actor is in on the joke but is also taking her role very seriously.

Is “Madame Web” a good movie? No. Is it hilariously delightful? Often. The film follows an obscure Marvel character who has the ability to see the future because she was bitten by a poisonous spider in utero while her mom was researching spiders in the Amazon. The year is 2003 for some reason, probably having to do with the age of a future Peter Parker, that other kid famously bitten by a spider. Johnson plays Cassie Web, a FDNY paramedic in Queens, whose main personality trait is “mean to children.” The screenplay pins her social awkwardness on the fact that she grew up in foster care, after being born in a mystical grotto in Peru while her mother, Constance (Kerry Bishé), died in childbirth.

Constance was, of course, researching spiders in the Amazon — as one does — before her security guard, Ezekiel (Tahar Rahim), turned on her, shooting the team of researchers and stealing the spider and its magical peptides. Though wounded, a heavily pregnant Constance is rescued by a secret team of indigenous Peruvian “spider men” known as “arañas,” but they can only save the life of the baby.

Evil Ezekiel, meanwhile, hoards the spider peptides for himself, and 30 years later, he’s now a sort of cursed dark Spider-man, tormented by premonitions of being killed by a trio of spunky Spider-women. He attempts to track down these future assassins using surveillance tech pilfered from the NSA, which is commandeered — wait for it — by Zosia Mamet of “Girls.”

Cassie is having her own terrible, horrible, no good, very bad week. First, she plummets into a river while saving a passenger in a car wreck, triggering a hallucinatory near-death experience. Then she starts having terrifying visions and harrowing déjà vu, which leads to her inadvertently abducting three teenage girls from a Metro-North train in order to save them from Ezekiel’s dark Spider-man. To evade Ezekiel, she’ll have to harness the previously unknown powers of her peptide-enhanced mind.

As Cassie, Johnson is so compellingly weird that you can’t take your eyes off her. She delivers every clunker of a line with her full chest voice and a twinkle in her eye. The three other gals — Sydney Sweeney, Celeste O’Connor and Isabela Merced — well, they were clearly cast for a potential future standalone film, which has to be DOA at this point. They’re all a bit awkward and forced, and none are working on the galaxy-brain level of Johnson.

Sontag wrote that to talk about camp is to betray it, and she’s right. It’s impossible to persuasively describe the bad-good charms of “Madame Web,” an appreciation of which requires the kind of sensibility that celebrates the unnatural, the artificial, the exaggeratedly “off.” Johnson gets it, and for those who do as well, it’s kind of a thrill to get tangled in her web.

Katie Walsh is a Tribune News Service film critic.