“Lisa Frankenstein” is a gross-out horror comedy that succeeds only partially. It’s not funny or horrifying or fantastic, but it is disgusting, with a romantic lead who stinks — literally — and has worms dropping off of him.

Screenwriter Diablo Cody (“Young Adult,” “Tully”) gave first-time director Zelda Williams a bad hand to play, and Williams — the daughter of Robin Williams — overplayed it. Actors are encouraged or allowed to mug, preen and go over the top, as though every moment were hilarious. But every moment isn’t. Cody has always been a reliable screenwriter, but aside from a single line (a reference to a perfume by Elizabeth Taylor), there’s no evidence of her usual wit.

Set in 1989 for no particular reason, the movie tells the story of Lisa, a high school student whose mother was murdered in a home invasion. Her father has since remarried, and now Lisa lives in a house with a toxic stepmother (Carla Gugino) and an unusually warm and generous stepsister (Santa Clara native Liza Soberano), a cheerleader who tries to integrate Lisa into her social circle.

Lisa, however, just enjoys taking walks in a creepy cemetery, and one night, through some accidental conjuring, she is able to bring a young man (Cole Sprouse) back from the dead. Considering he has been in the grave for 150 years, he’s doing OK. He’s just missing a hand, an ear and a penis, but you know how Frankenstein movies are — missing parts can always be replaced.

From that point on, “Lisa Frankenstein” becomes the story of all the wacky things that happen when a high school girl decides to hide a reanimated stinking corpse inside her closet.

As a director, Williams doesn’t find a steady tone through which to tell the story. The movie’s erratic and scattered nature may largely be the fault of the screenplay, but not entirely. In Williams’ hands, individual scenes don’t cohere with other scenes. Her directorial default seems to be to treat most moments as though the story and characters are completely pointless and don’t matter, which is plainly true, but a filmmaker’s job is to make you not notice.

Neither Cody nor Williams nor Kathryn Newton (“Freaky,” “Pokémon Detective Pikachu,” “Ant-Man and the Wasp: Quantumania”), who plays Lisa, can make any sense of Lisa’s abrupt transition, at a certain point, into a cold-blooded murderer. They just present it and expect the audience to continue to root for her as a high school underdog.

In one of the movie’s most ham-fisted directorial touches, a supposedly comic murder scene is followed by a supposedly tender scene, in which Lisa sews a new hand onto the corpse’s stump. Williams underscores this with a piano and violin playing softly and romantically, with no hint of irony.

Newton seems to have some residual charm, but it’s mostly smothered by her strenuous attempts to be funny. And, needless to say, as the grunting corpse, Sprouse doesn’t get to do much other than make faces, though he showed himself to be an appealing actor in “Five Feet Apart” (2019).

The only thing to take from the wreckage of “Lisa Frankenstein” is the performance of Soberano, in her Hollywood debut. She finds comedy in a weak script and radiates goodness without being boring. Let’s hope she has better movies in her future.

Reach Mick LaSalle: mlasalle@sfchronicle.com