Plot

A group of friends gather for a pre-wedding party that descends into an existential nightmare when an estranged friend arrives with a mysterious game that awakens long-hidden secrets, desires and grudges.

Couple Shelby (Brittany O'Grady) and Cyrus (James Morosini) and their friends Reuben (Devon Terrell), Dennis (Gavin Leatherwood), Nikki (Alycia Debnam-Carey), Brooke (Reina Hardesty), and Maya (Nina Bloomgarden) gather at Reuben's family home for a party before Reuben's wedding. Nikki is a social media Influencer. Shelby and Cyrus are having issues in their relationship as Cyrus would rather masturbate, than have sex with Shelby. Shelby tries to emulate Nikki's profile in her own accounts, but she barely gets any likes. Nikki is allergic to peanut butter.

Also due to attend is their mutual friend Forbes (David Thompson), whom they have not seen since a party at college for which Forbes got expelled for bringing his high school student sister Beatrice (Madison Davenport). Beatrice, obsessed with Dennis, who was dating Nikki, was admitted to a mental facility. Forbes and Dennis got into a scuffle at that party before the police arrived. Forbes was a genius and got the Freshman grant as well. He was famous for putting on game nights. After the party, Forbes went to California to work in a Technology company 8 years ago.

Forbes arrives at the party, carrying a suitcase. Inside the case is a device that allows them to swap bodies with one another. Forbes explains that he and his colleagues would use it to play a game where they have to guess who is in their bodies. After doing a short demonstration on the group, they all eventually agree to participate, taking Polaroid photos for identification. The machine requires wiring to be done to determine who goes into whose body. Forbes programs the machine and thus knows who goes into whose body.

When round 1 begins, Shelby is immediately found to be in Brooke's body. Every time someone is identified, they have to stick their correct identification on the body they are in. Reuben is in Cyrus's body as he objects when the person in Reuben's body decides to drop his pants. Maya is found to be in Nikki's body as she says "dude" . The group incorrectly guesses that Cyrus is in Dennis' body. To Cyrus' (who is actually in Reuben's body) surprise, Forbes, who is the one in Dennis' body, plays along with the lie, pretending to be Cyrus. Deciding to play along himself, Cyrus (in Reuben's body) encounters Maya who is in Nikki's body, and the two kiss.

Dennis reveals to Forbes that back in college, Reuben had joined Dennis in complaining against Forbes and getting him expelled for bringing his high school sister to a college party.

Unnerved by Forbes' lie, Cyrus declines to take part in round 2 but relents after the initially timid Shelby eagerly agrees to take part. Cyrus and Shelby come up with a signal (rubbing their eyebrow) to indicate which body they are in, just in case something goes wrong.

Forbes explains this will be the last round before the machine takes 24 hours to recharge. When the round begins, Shelby swaps into Nikki's body and is quickly enamored by her good looks and successful social media career. Cyrus, who is in Forbes' body, signals to all the girls but none of them return his signal. Later he finds Shelby in Nikki's body and they decide to have sex. But, as things get too intense, Cyrus (in Forbes' body), backs out. He believes that Shelby wants to have sex with Forbes.

Cyrus (in Forbes' body) panics and demands they end the game. As the group gathers in the house to switch back, the house's rooftop balcony collapses, and Reuben in Dennis' body and Brooke in Maya's body, who were up there having sex, fall to their deaths.

Arguing over what to do, Forbes refuses to let the group call the police and let the device go into their custody. Dennis, furious at the suggestion he has to swap into Reuben's body, argues with Cyrus and reveals Cyrus only settled for Shelby as he could not date Nikki. Cyrus retorts that Dennis made nothing out of his life as he had his trust fund for sustenance.

Dennis calls the police, claiming that Cyrus has killed Dennis and Maya. Forbes attempts to flee with the device but is subdued by Nikki (In Brooke's body). Shelby refuses to swap back and leave Nikki's body. Apart from Forbes, Shelby is the only one who knows how to work the machine, so unless she agrees, everybody is stuck in the bodies they are in as Forbes is knocked out.

Cyrus tries to make amends with Shelby, but Maya (in Shelby's body) tells Shelby that Cyrus had kissed her during the first round of the game while he was pretending to be Forbes, and she was in Nikki's body. Forbes awakens, and Nikki tries to convince him to make the swap.

Shelby appears, threatening to ruin Nikki's career with a damaging video. Shelby proposes that if Cyrus wants Nikki, then she can stay in Nikki's body, and he can go into Reuben's body, while Dennis, in Cyrus' body, takes the fall for the deaths. Nikki allies with Forbes to swap back into their original bodies, and Nikki makes Shelby have an allergic reaction to peanut butter, refusing to give over the EpiPen unless Forbes checks the wiring. Dennis discovers money from his trust fund has been transferred into an offshore account and accuses Cyrus. The police enter the house just as the group sets off the device.

The next day, Beatrice arrives at the house to discover the wedding has been called off and attacks Forbes' body. Seeing Dennis in Forbes' body, she reveals that she is the real Forbes (and that Beatrice had stolen his suitcase, the one with the machine), and that Beatrice had swapped bodies with him to enact revenge on Dennis and Nikki. Forbes had visited Beatrice in the hospital and showed her the machine, as a way of reconnecting with her.

In the aftermath, Maya is in Brooke's body, Shelby and an imprisoned Cyrus have returned to their bodies, Nikki is in Reuben's body, while Beatrice, now in Nikki's body, escapes with Dennis' money and the device. Shelby refuses to clarify the truth to the cops as she was mad at Cyrus for agreeing that Shelby could remain in Nikki's body for the rest of her life.