Matthew, a successful investment banker, assesses the new arrivals with contempt. Already seated are Janet, a lingerie company managing director; Melvin, a Welsh police officer; Stella, a fashion YouTuber; and Dr. Gordon MacMillan, a television nutrition expert. Melvin enthusiastically greets Vivienne and Tristan and introduces everyone, noting the absent host.

Matthew introduces himself with a calculated smile. He reflects on his manipulative nature, both at work and in his personal life, where he preys on vulnerable women from dating websites, making them dependent before abandoning them. He was recently featured in an article about London’s most eligible bachelors. Though he’s already decided to pursue Stella, he confidently wins Janet over, placing his arm on her chair. His phone buzzes with messages from multiple women he’s manipulating.

Gordon remarks on Melvin being both Black and Welsh, which Melvin defuses with humor. Waiters serve wine. Janet initiates a flirtatious game of “Snog, Marry, Kill” (13) with Matthew. When Gordon requests water, Janet rolls her eyes. Matthew notices his place card features a drawing of a sheep looking at a ewe. As he pours more wine for Janet, he reflects that red wine has always looked like blood to him.

Stella Cooke watches Matthew flirt with the older Janet and wonders why he bothers with her. She recognizes Matthew from a magazine article about eligible bachelors and notes his financial potential as her wealthy father is “threatening” to stop giving her money. She’s frustrated Matthew hasn’t looked her way and feels disappointed by the dinner party. She’s still angry about Gordon’s comment to Melvin.

She checks her YouTube channel, StellaStylez, where her latest video about cowboy boots has garnered praise from her nearly half-million teenage subscribers. Though she privately thinks affordable fashion can’t compare to designer items, they believe anything she says. She then logs into her secret trolling account, feeling exhilarated by the hateful comments she’s left for others.

When Vivienne asks about her work, Stella boasts about her subscriber numbers. Gordon mentions his 14-year-old daughter watches vlogs. Janet recognizes Gordon from television and jokes about celebrity diets. Stella stops listening, then gets excited when Matthew engages her. He shows her how to tell if the wine is good, then she spills her own trying to swirl it. She begins to feel intoxicated and enjoys it. Janet then asks Matthew if he is single, and he winks at Stella across the table, exciting her.

Tristan stares at his fingernails, overwhelmed by the dinner party chatter. He hasn’t spoken to anyone face-to-face in five days and wants to retreat to his flat in Manor House. He observes Vivienne’s disgust at Janet’s loud personality and recalls how Vivienne dismissed him when they met on the street.

He instinctively touches the boomerang-shaped scar on his cheek, left by a “thug’s boot,” and feels self-conscious about his Metallica T-shirt and receding hairline. He reflects on a recent phone call with his overbearing mother, who mentioned his ex-girlfriend Ellie and reminded him his father is coming to fix his boiler. He thinks about living at home after the breakup and discovering a secret box under his parents’ bed.

Tristan mutters that the evening “reminds [him] of a Murder Mystery night” (24), but no one hears. He notices his place card shows a bulldog with a balled fist and calms himself by counting prime numbers.

Waiters serve foie gras. Gordon confirms the dish contains no sesame seeds due to his allergy. When Tristan struggles with the crumbling crackers, Melvin suggests using spoons instead, and they bond over their unfamiliarity with fancy food. Despite its appearance, Tristan finds the foie gras delicious.

Melvin makes small talk, revealing his wife Mary is recovering from chemotherapy. When Tristan tries to sympathize, Melvin cuts him off and requests more wine. Tristan notices Melvin’s looks guilty rather than sad when talking about her.

Gordon watches Janet devour her foie gras with a mixture of disgust and arousal. He reflects on the dish’s nutritional content and his philosophy of moderation. Thinking back to medical school autopsies, he imagines cutting through the fat on Janet’s body.

He eats his portion slowly, chewing exactly 32 times, and after taking a second cracker forces himself to stop. His place card identifies him as Dr. Gordon MacMillan and features a peacock drawing, making him hope this is a “high-profile” speakers’ event. When Janet requests his leftovers, he pulls the plate back.

Melvin encourages him to eat more. Gordon inwardly dismisses the rugby conversation between Melvin and Matthew. He brings up Melvin’s wife’s cancer and lectures him about how a healthy diet reduces cancer risk. Melvin snaps that Mary isn’t obese. Vivienne cuts in with a look that reminds Gordon of his wife Elizabeth’s warnings about his lecturing.

He reflects on Elizabeth’s cautions and thinks about his daughter Louisa’s developing body, how he tries to warn her about fatty foods when Elizabeth isn’t around. He loves his television work and hoped to network tonight.

Gordon realizes with horror he’s eaten all his foie gras. Feeling unbearably hot, he excuses himself to the restroom, locks himself in a cubicle, and crouches before the toilet. Hearing footsteps, he quickly flushes to cover any sound, then returns to the dining room after checking the corridor is empty.

Janet gazes at Matthew, feeling “alive for the first time in months” (33). She recalls that morning’s silent breakfast with her husband, Bill, an overweight 60-year-old who ignored her new dress. When Bill asked her to call his sister about their niece’s christening, it resurfaced her pain about being childless. He commented her dress was too tight and she should use her gym membership. Furious, Janet comforted herself by imagining Bill dead, picturing herself as a sexy young widow.

The group speculates about the absent host. Melvin suggests they might be on reality TV. When the main course, Chateaubriand, is served, Janet savors the steak. She notices her place card shows a pig eating a roast dinner and quickly hides it in her bag.

Vivienne recognizes Janet from an interview years ago for a Women in Business feature. Janet recalls the encounter, which happened after she sold her clothing app for a large sum, firing staff she’d encouraged to invest. The resulting article criticized her ruthless business practices and her lingerie brand’s objectification of women.

They have a tense exchange about plus-size models. Janet tries to get Matthew on her side by asking who wants to look at “big girls” in their bras. Matthew replies he likes “curvy” women while looking suggestively at Janet. Everyone looks at her silently as she realizes he’s talking about her.

Melvin sees Matthew’s “curvy girl” comment hit its mark with Janet. He contrasts Janet’s behavior with his wife Mary’s dignity during her cancer treatment. Janet deflects by mentioning Kim Kardashian.

Melvin reflects on a recent domestic murder case where he felt shameful sympathy for the husband who killed his wife. His thoughts turn to his consuming attraction to his colleague Christian. He recalls hoping the dinner party was a secret date arranged by Christian.

He recognizes Stella from a burglary report he took at her Kensington flat, where she was too drunk to give a statement and argued with her father about expensive jewelry. He notices she’s now wearing a similar diamond necklace.

Waiters serve chocolate dessert. Mini black envelopes suddenly appear beside each wineglass. Janet opens hers, her smile freezing as she throws the card on the table in panic. Vivienne picks it up and reads that it predicts Janet will die at 44. The atmosphere turns “suffocating.”

Vivienne discovers the kitchen door is locked. Gordon opens his envelope, revealing his number is 53. Matthew quickly opens his, glancing at the card before putting it away. Vivienne and Tristan refuse to open theirs. Janet sobs, revealing she’s already 44 with her birthday in July, calling it a death sentence. Stella chuckles then covers it as a cough.

Melvin collects everyone’s contact details and reassures them. The guests gradually leave, with Vivienne and Tristan taking their unopened envelopes. Two unopened envelopes remain on the table. Melvin asks the distraught Janet if she wants another drink.

Two weeks later, Vivienne watches her junior colleague Cat cry over edited work. She reflects on Cat’s tears as manipulation and recalls her own early career struggles as the only female writer, being excluded from male colleagues’ pub lunches. She remembers the one time she cried at work after her ideas were dismissed; her boss warned her never to show emotion again.

Vivienne scolds Cat and threatens to give her section to intern Lauren. At her desk, she finds an email from Melvin Williams to all the dinner guests reporting that Serendipity’s isn’t registered and, more importantly, that Stella Cooke died at 23 after falling in front of a tube train. Vivienne replies, questioning the circumstances and asking who owns the building, while Janet answers panicked about Stella’s number. Gordon claims he has “significant” information and proposes meeting at Stella’s funeral.

Vivienne recalls leaving Serendipity’s feeling sluggish with a dead phone battery. Tristan helped her gather her spilled belongings and walked her to the tube station. The mystery haunted her for days.

Last Friday, Vivienne experienced a fugue state, losing five hours and ending up on a train to Heathrow. The experience reminded her of a similar episode at 18 following a traumatic event she’s never discussed. Searching her handbag, she discovered her envelope was missing.

Looking at Stella’s photo, Vivienne feels irresistibly drawn to solve the mystery and decides to attend the funeral.

Matthew arrives at Stella’s funeral, surprised by crowds of teenage fans and photographers. Janet greets him effusively, asking if Stella mentioned opening her envelope since they left together. Matthew has a panic attack, overwhelmed by Janet’s perfume. He recalls his disappointing night with Stella. Unimpressed by his wealth, she left after lackluster sex, suggesting they might meet again unless her number proved correct.

Stella’s parents arrive, having a loud argument about who was to blame for their daughter’s unhappiness. Vivienne suggests going to a nearby wine bar instead. Melvin and Gordon join them.

Matthew thinks about the night after the dinner party. He went on a date with Robyn, a woman he was manipulating, but it was ruined by an old high school bully. That night, he had nightmares about childhood bullies and the abusive uncles his mother brought home.

A few days later, Gareth blackmailed him on Facebook with an old class photo. When Matthew read about Stella’s death, he became convinced her number was 23. He had a severe panic attack and fled to his office rooftop, terrified his own number was approaching. Despite planning not to attend, he found himself pulled to the funeral.

At the wine bar, Tristan observes the group has sat just as they did at Serendipity’s, with an empty chair for Stella. Matthew’s demeanor has changed to “gloomy.” The group discusses Stella’s death and her recently revealed secret trolling account. When the waitress gets Tristan’s drink order wrong, he silently counts to control his frustration.

As Vivienne takes notes, Melvin makes a dismissive comment about her amateur investigation. He reveals that the Serendipity building is rented out for events, but he’s struggling to find the owner. Tristan recalls Melvin and Janet whispering together at the end of the dinner party. After leaving, he found Vivienne outside Serendipity’s, disoriented, so he walked her to the tube station. After walking home feeling energized, he logged onto Facebook and discovered his ex-girlfriend Ellie had unfriended him, which deeply upset him.

In the present, Tristan notices that Melvin seems happier than at the dinner party. Melvin returns with shots for everyone. Tristan makes a toast to Stella and forces down the aniseed-flavored drink.

Gordon takes the tiniest sip of his shot and hides the rest. He announces it’s time to discuss his information and produces Stella’s black envelope from his pocket. After the dinner party, he picked up Stella’s and Melvin’s leftover envelopes. He followed Janet and Melvin to a hotel bar and watched them from outside.

The next morning, hungover, Gordon purged the meal from the night before. His wife Elizabeth caught him, and they argued about his relapsed bulimia. The incident made him falter during his next live TV appearance on The Morning Show.

After receiving Melvin’s email about Stella’s death, he remembered the envelopes and saw that Stella’s had already been opened. He put Melvin’s unopened envelope in his desk drawer. He developed a theory about the dinner party and decided to lure the group together again.

In the present, the group stares at the envelope in horror. Janet notes it’s been opened; Gordon claims it was like that when he found it. Gordon picks up the envelope to reveal the number, but Janet slaps his arm. Gordon is confused by their resistance, believing knowing the number is crucial. Tristan suggests Melvin should take it to the police station.

Janet stares at Stella’s envelope, her heart racing as she remembers her own prediction. After leaving the dinner party with Melvin, they went to a hotel bar where he confessed he was falling in love with a male colleague. Needing distraction, Janet left and went to her lover Giles’s apartment, resuming their affair she’d recently ended. She went home late, sleeping in the spare room with nightmares.

Days later, Bill tried to plan her 45th birthday, which sent her into a panic with stomach cramps. She reflected on how the fear from the prediction card hadn’t subsided but had “settled […] like a rumbling volcano” (85). A few days later, her big fashion show was a disaster after she was caught performing oral sex on the financial director to cover up her expense fraud. Reading Melvin’s email about Stella’s death, she felt a flicker of revenge because Matthew took her home, but then fear about the numbers returned. When news of Stella’s trolling broke, Janet found she liked Stella more for it.

In the present, looking at the envelope, Janet feels nauseous. She tells the group she needs a minute and warns them not to touch the envelope while she’s gone.

Melvin is distracted by a text from Christian confirming their first date for the next day. He feels guilty for being happy on the day of Stella’s funeral. Janet returns and whispers, asking if he’s told his wife yet; he says he plans to that night. He remembers his drunken confession to her in the hotel bar.

Last week, Christian confessed mutual feelings, and they planned for Melvin to end his marriage to Mary that night. A waitress brings champagne ordered by Janet, who toasts Stella.

Gordon analyzes the facts, confirming Janet is 44 and his own predicted age of death is 53. Vivienne’s envelope is missing, Tristan hasn’t opened his, and Melvin claims he doesn’t know where his is. Matthew lies, saying he left his at Serendipity’s.

Gordon grabs Stella’s envelope and pulls out the card. Matthew snatches it and drops it on the table: It predicts she will die at 23. Gordon suggests they must wait and see if another prediction comes true. Janet has another panic attack.

Vivienne theorizes one of Stella’s trolling victims is seeking revenge. Melvin agrees to investigate. He shuts down Gordon’s attempt to offer another theory and urges everyone to throw away their envelopes. The guests gradually leave.

Alone with Matthew, Melvin confronts him, saying he saw him open his envelope at the dinner party. Matthew confesses his number is 29 and he’s terrified, as he turns 30 in three months. Melvin tries to reassure him it’s just coincidence. They say goodbye, and Melvin texts Mary that he’s on his way home.