A "difficult-to-watch" new body horror movie featuring "barbaric" cosmetic surgery has already made one person throw up at Sundance

A new body horror movie inspired by Cinderella has debuted at Sundance, and it's already made one person throw up.

The Ugly Stepsister, written and directed by Emilie Blichfeldt, focuses on Lea Myren's 'ugly' stepsister who undergoes a grisly transformation in the hopes of winning the prince.

Variety writes that, during the premiere, one audience member vomited into the aisle, and the report describes "several difficult-to-watch scenes of crude cosmetic surgery, including its protagonist eating a tapeworm, sewing in eyelashes and enduring a barbaric rhinoplasty."

"Someone literally threw up in the aisle during the premiere screening of THE UGLY STEPSISTER at #Sundance. If that’s not a ringing endorsement, I don’t know what is," says Next Best Picture's Matt Neglia. "But I'll just add, this sinister take on the classic Cinderella story is grotesque, beautiful, and twisted in its examination of the pursuit of beauty at all costs. Lea Myren goes to some truly horrific places with her pained performance, eliciting winces and groans of sick delight from the audience."

"Mighty impressed by The Ugly Stepsister! It's The Substance meets Raw for period fairytales. Sick, twisted, and delightfully gruesome, this unhinged take on Cinderella from her stepsister's POV delivers audience-squirming body horror chaos at its finest," writes Jason Osiason of Fantastic Film Fans. "Explores the relentless pursuit of beauty and idealized romance, exposing the dark consequences of obsession. Penetrating use of stomach-grumbling sounds, and one unforgettable scene at the end destined to be remembered for its sheer visceral intensity!"

"THE UGLY STEPSISTER takes Grimm and makes it gruesome. A reimagined Cinderella story told from the stepsister's perspective, this is a darkly comedic and often groan-inducing experience. Put on your glass slippers and get ready for the blood and social commentary," writes Mainely Movies.

"THE UGLY STEPSISTER: The Substance meets Cinderella in this squirmy retelling of the classic tale from a much darker perspective. A truly fearless, physical lead performance from Lea Myren that might be hard to top at Sundance this year," says RogerEbert.com's Brian Tallerico.

Another body horror movie, The Substance, just picked up Oscar nominations for Best Picture and Best Actress for Demi Moore.

While you wait for The Ugly Stepsister, check out our guide to the year's most exciting upcoming movies – or check out our guide to the Oscars 2025 nominations in full.