Spoiler alert! We're discussing major details about the plot of the new movie "Kinds of Kindness" (in theaters now).

Emma Stone is back with another squirm-inducing curio.

“Kinds of Kindness” is the actress’ fourth collaboration with director Yorgos Lanthimos, just months after their freaky Frankenstein film "Poor Things" netted Stone her second Oscar for best actress. Clocking in at nearly three hours, the pitch-black comedy is split into three loosely linked stories, all featuring a core cast of actors playing different roles.

The most intriguing tale is the provocative middle section, “R.M.F. Is Flying,” which puts a deranged twist on the true-crime genre. In the roughly 40-minute film, a stilted police officer named Daniel (Jesse Plemons) is thrilled when his missing wife, Liz (Stone), returns after a research expedition gone haywire. But soon, Daniel starts to suspect that the woman in his house isn’t the real Liz, but an imposter. He begins to test her devotion: first, by ordering her to chop off her fingers and cook them for dinner. When she obliges, Daniel takes it even further by demanding that she cut out her liver.

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The mind-bending mystery stemmed from conversations between Lanthimos and co-writer Efthimis Filippou, who wanted to explore relationships and memory. “You can sometimes forget people that you love and you don’t recognize them anymore,” Lanthimos says. “At some point, I had written this little thing about a woman offering parts of herself to someone to show her love. So as we were discussing the film, we felt these ideas together made sense.”

Jesse Plemons, Emma Stone worked with intimacy coordinator for 'weird' sex scene

In the other two sections of “Kinds of Kindness,” Plemons, 36, plays a cult member and a submissive businessman. But he says Daniel was the character he felt least confident about taking on.

“He was hard to peg, which I really liked,” Plemons says. “He was really hurting at the beginning, and those feelings of his partner vanishing could have stirred up any number of things.”

The most cringingly funny part of “R.M.F. Is Flying” comes at the beginning, when Daniel invites his swinger friends Martha (Margaret Qualley) and Neil (Mamoudou Athie) over for dinner. Afterward, he awkwardly asks them to watch a homemade sex tape they made with Liz.

“He just wanted to relive the good old days. The simple times!” Plemons jokes. The Oscar-nominated actor says he was initially nervous to shoot the graphic group scene. “You know it’ll be a little weird,” he recalls. But on the day, “it was just the actors, Yorgos and the intimacy coordinator in the room. It’s inevitably a little uncomfortable, but the intimacy coordinator walks you through the conversations you need to have so everyone feels safe.”

The end of 'R.M.F. Is Flying' is meant to be 'ambiguous'

Raunchiness aside, the film’s gruesome images may prove challenging for some audiences to stomach. After agreeing to slice off her fingers (in reality: silicone replicas), Liz reluctantly decides to carve out her liver and serve it for dinner. The prop used in the movie is an actual animal organ. (“Pig or cow liver, I don’t remember which,” Lanthimos says.)

“R.M.F. Is Flying” ends with Daniel walking into the kitchen, where he discovers Liz dead on the floor, having bled out after attempting to extract her liver. The doorbell rings, and Daniel greets another Liz (also played by Stone) with a warm embrace. The final moments are left purposefully vague: Did Daniel gaslight his actual wife into killing herself? Or was that an imposter in his home all along?

“I don’t think there’s a wrong interpretation or answer,” says Plemons, who won best actor at Cannes Film Festival last month for his performance. “It can change from viewing to viewing – it even evolved for me while we were shooting. But for me personally playing Daniel, I had to feel like he was right and she was an imposter.”

For most of the film, viewers are in Daniel’s shoes watching Liz’s strange behavior: She struggles to fit into her heels, and ravenously devours chocolate cake (a food she previously hated). But as the story goes on, Liz grows concerned for Daniel’s mental health, and he becomes increasingly deluded. Viewers are left discombobulated and unsure of whom to trust.

“It really is ambiguous in that sense of, ‘Who’s right? Is it happening in their heads? Are they both right?’ ” Lanthimos says. “That’s why we found it an interesting story to tell, and allow people to ask themselves those questions.”