One of the funniest things about Mary Shelley’s “Frankenstein” is how unfunny it is. Who can stifle a snicker at the monster’s first chat with his creator? “Oh, Frankenstein, be not equitable to every other and trample upon me alone, to whom thy justice, and even thy clemency and affection, is most due,” the brute exclaims. Say what? He’s meant to be made from the spare parts of dead guys, but he talks like Mr. Darcy. In a way, Shelley’s novel has to be humorless. (Don’t forget that she was still a teen-ager when she wrote it.) One prick of a joke and the grandeur of her tragic tale—the Alpine sublimity of it all—would go pop.

No such caution attends the new movie from Yorgos Lanthimos, “Poor Things,” which is best approached as a rumbustious riff on Frankensteinian themes—or, in the pensive words of one character, “this diabolical fuckfest of a puzzle.” The creature at its core is Bella Baxter (Emma Stone), a young woman who—for reasons that I shan’t reveal—comes under the care of Dr. Godwin Baxter (Willem Dafoe). “Her mental age and her body are not quite synchronized,” he says. Initially, Bella expresses herself in guttural blurts and wild linguistic lunges: “Bud,” she declares, having whacked a man on the nose and drawn blood. Lanthimos charts the gradual improvement in her synchronicity, as her understanding blossoms from the childlike into the mature. If that makes the film sound like no fun at all, don’t worry. Only very rarely is it not fun.

“Poor Things,” written by Tony McNamara, is based on a 1992 book of the same title by the Scottish novelist Alasdair Gray, who died in 2019, and who didn’t so much spin yarns as weave them into complex—and magnificently unreliable—tapestries. He was a Glaswegian and a specifier, and on the page it is briskly stated that Baxter, a surgeon residing at 18 Park Circus, Glasgow, first encounters Bella in February, 1881. Onscreen, matters are less precise. The city is unnamed, and, as for the period, my guess would be late-Victorian steampunk, tricked out with modernist gewgaws. When Bella goes to Portugal, we see trolleys arcing through the sky on wires, like neighborhood airships. Time, in short, is a jumble.

But then almost everyone here, and everything, is constructed from bits and pieces. Consider Godwin Baxter, whose face is a roughly cut jigsaw of flesh, and whose Scottish accent wavers like a candle. His home has an operating room and an unusual menagerie, including a bulldog with the back end of a goose. The dog’s rump is attached to the front of the bird, and the result trots happily along. Baxter’s carriage is a horse’s head melded onto a juddering steam engine. These living collages are his proud handiwork, and Bella is his masterpiece. He’s like Victor Frankenstein minus the tortured conscience—a hyper-rational product of Enlightenment truth-hunting, splendidly played by Dafoe with a fierce benevolence, and without a shred of silliness. After lecturing students in anatomy, he invites the most promising of them, Max McCandles (Ramy Youssef), to be his assistant, and to document Bella’s progress.

Sadly, we miss out on the fabulous pun cluster with which, in Gray’s book, Bella greets Baxter and Max together: “Hell low God win, hell low new man.” It’s like the plot of “Paradise Lost,” boiled down to eight monosyllables. (The philosopher William Godwin was Mary Shelley’s father, and, in the movie, Bella often addresses Baxter simply as “God.” You getting all this?) In most respects, however, Lanthimos is loyal to Gray’s vision of Bella as much more than a scientific curiosity—as someone through whose eyes and on whose inquisitive tongue the world is forever being tested and tasted, as if it were freshly made. Bella doesn’t have bad manners; rather, when she bumps into the laws of social conduct, she forces us to reassess how rum they can be and to wonder why we bother with them at all. On board an ocean liner, Bella approaches a passenger and cries, “Hello, interesting older lady!,” patting the woman’s frizzy hair to gauge its texture.

The narrative thrust of the film is itself a joke, being a parody of Romantic melodrama, and relying on what Bella calls “a confluence of circumstances I regard as almost fate-like.” Although Max (a gentle man, if not quite a gentleman) is attracted to Bella, and proposes marriage, he is trumped by an incoming cad named Duncan Wedderburn, played by Mark Ruffalo with a mustache, a calculating smirk, and a barrel-load of glee. Scooping up Bella, Duncan bears her off to foreign climes and schools her in mischief, only to be outsmarted by her fast-blooming intelligence. As she informs him, “my heart has become dim towards your swearing, weepy person.” Would that all relationships could be broken off with such forensic frankness. The action shifts to Lisbon, Alexandria, Paris, and finally back to British shores. There, in proper nineteenth-century fashion, a devilish twist awaits.

One of the funniest things about “Poor Things” is the headline that appeared in Variety after the film’s première at the Venice Film Festival, on September 1st: “Emma Stone’s Graphic ‘Poor Things’ Sex Scenes Make Venice Erupt in 8-Minute Standing Ovation.” Laying aside the giveaway verb—no eruptive dysfunction here—one can but marvel at the blush of puritan shockability in such a response. It’s a charming idea that the audience was stirred not by any dramatic skills on the part of the leading lady but exclusively by her valor as she dared to feign the gymnastic arts of love.

There is indeed a fair dollop of carnality in Lanthimos’s movie, but it’s hardly a torrent. “Furious jumping,” Bella calls it, in a fine example of her poetic plain speaking, and, having sampled it, she wants more. Sprawled in postcoital languor next to Duncan, she asks, “Why do people not do this all the time?,” an excellent question to which I, like Duncan, have no satisfactory reply. What matters most is that the sex, pace Variety, is not some isolated bout of friskiness; it takes its place in a larger comedy of appetites, as Bella hungers to steep herself in experience. If she dislikes a mouthful of food, she spits it out. When she dances, she jerks like a doll gone mad.

Lanthimos, one might say, has been here before. In his breakout work, “Dogtooth” (2009), two sisters gesticulated and shuffled in front of their parents as if obeying some absurdist ritual. And did Stone not display a Bella-like deadpan candor in “The Favourite” (2018), Lanthimos’s previous feature? Yes, but here she is more forthright still, pacing the metamorphosis of her character with warmth and wit. “The Favourite” felt arch and knowing, whereas “Poor Things” is about the act of knowing, and, much as Boris Karloff uncovered tenderness in horror, Stone takes a cautionary fable of the early machine age and crowns it with a generosity of spirit—aided, it must be said, by Holly Waddington’s sumptuous costume design. Check out Bella’s sleeves. They are not merely puffballs. They are explosions.