On Sunday night, Demi Moore debuted in the official selection of the Cannes Film Festival, playing the role of The Substance in the competition. The highly awaited blood-splattered horror movie directed by Frenchman Coralie Fargeat received a 13-minute standing ovation, the longest for a title at the festival thus far.

From the moment the film’s credits rolled on screen—which also features Margaret Qualley and Dennis Quaid—the audience clapped enthusiastically. It’s being marketed as a feminist spin on a body horror film, with a focus on a new substance called The Substance that claims to change users into the most amazing versions of themselves. There is a catch to this offer.

The Substance premiered twenty minutes later than scheduled, but by the time it ended, at around one in the morning, there was raucous cheering for Moore’s major comeback film.

The reaction seemed to excite Moore, Qualley, and Fargeat, as Moore kissed the screen and exclaimed, “Thank you! Thank you!”

Moore mentioned that it was Forgeat’s first time directing a film at Cannes, and she added, “Merci Master Thierry,” a reference to Thierry Fremaux, the head of Cannes. In her succinct statement, she added, “It has been an incredible ride,”

The Substance’s official summary states: “It generates another you. A new, younger, more beautiful, more perfect you. And there’s only one rule: You share time. One week for you. One week for the new you. Seven days each. A perfect balance. Easy. Right? If you respect the balance… what could possibly go wrong?”

Prior to the festival, Mubi obtained the film’s worldwide rights; this was a significant night for the business as it expands its in-house theatrical distribution division under the direction of new distribution chief Mark Boxer.

Moore discussed navigating Hollywood as an older actress earlier today while walking her adorable dog Pilaf. She said, “You just show up and you face what’s in front of you to the best of your ability. I think what’s most important is how you hold yourself not how the world is holding you… which is exactly what The Substance is about – this male perspective of the idealized woman, that we as women have bought into… and I think we are changing. We are living the change right now.”

In addition to her presence on the red carpet with The Substance, Moore is occupied this week as the host of amfAR’s 30th anniversary Cannes gala on Thursday and as godmother for Chopard’s Trophée Chopard gala ceremony.