Parties are dramatic. Maybe it's a Wild Teen Party, a Surprise Party, a Masquerade Ball even a Plutocratic Pervert Party. Or maybe it's simply an (apparently) civilized opportunity to meet and talk, or perhaps it masquerades as a Shoddy Shindig at least for some of its guests.
But, if they're mentioned — even, and often, especially, if it's mentioned offhandedly — something huge happened, or will happen, there. Maybe a Chekhov's Gunman was in attendance, or the party's subject receives a Chekhov's Gift. Whatever you learn about this party, due to The Law of Conservation of Detail, it will be important, and it will probably give you the answer to the mystery. Especially popular because Hidden in Plain Sight is especially easy to pull off in a room full of people who may or may not know each other, and that also makes this a gift for situations where Everyone Is a Suspect.
There are examples both where the protagonist is in attendance, which makes sense because generally, in the crowd, they may have witnessed a Meaningful Background Event whose full implications they don't yet understand. It's often more obvious when the protagonist isn't in attendance, because whatever they learn about the party will often provide them with the other inkling to help them realize, eventually, what happened there and why it matters.
What Did I Do Last Night? examples that involve parties traditionally won't count, because it's often obvious to the protagonist why the party is important. Compare and contrast Ten Little Murder Victims and Reunion Revenge, which often include a dramatic party, but frequently won't overlap with this because they are the main setting.
This is a spoiler trope. There will be unmarked spoilers, and often even knowing these incidents are significant constitutes a spoiler. Proceed with caution.
Examples
- All the Boys Love Mandy Lane: The first party where Emmet goads Dylan into jumping off the roof into the pool. You can see Mandy look at Emmet from the pool, giving him the go-ahead, which is an early hint that Emmet and Mandy are in on the massacre together, and won't be confirmed until Mandy kills Chloe.
- The Devil Wears Prada 2: Nigel tells Andy that Irv is due to announce Miranda as the head of global content to his media empire at the party celebrating Runway. The party happens in the next scene, and just as he's about to make the announcement, Irv drops dead from a Hollywood Heart Attack.
- Downton Abbey: The Grand Finale: The Petersfield party is mentioned a couple of scenes before the Crawleys go. It becomes the setting for Mary to be outed as a divorced woman, and Lady Petersfield throws her out when Princess Arthur arrives, establishing how Mary will be marginalised from much of high society.
- Draft Day: In the leadup to the draft, Browns GM Sonny Weaver's scouting staff tells him about presumptive top pick Bo Callahan's last birthday party, which none of his teammates attended. This, along with other revelatory character flaws, come up later on and serve to justify Sonny's decision to draft Vontae Mack instead of Callahan first overall.
- Final Destination Bloodlines: Early in the movie, Brenda and Julia talk to Charlie about his upcoming prom and his promposal to Jenny. At the end of the movie, Stefani comes back home for Charlie's prom and is accompanying him to Jenny's house when the two of them are killed by the derailed train.
- At the beginning of The Fugitive, Dr. Richard Kimble remembers that on the night he found his wife murdered by an intruder with one arm, he remembers being at the hospital benefit talking to some other doctors, when his best friend, Dr. Charles Nichols comes over and thanks him for letting him borrow his car, and returns his keys. At the very end, when he's cornered in the laundry room, pursued by U.S. Marshall Gerard and the Chicago Police Department, Gerard tells Richard the reason why the C.P.D.detectives determined he was guilty of killing his wife is because there was no forced entry. Which happened because Nichols drove to Richard's house, unlocked the door, called the one armed former cop to wait for Richard and his wife, who left the party early, and kill them by making it look like a robbery gone wrong.
- M3GAN 2.0: In Appleton's first appearance in the film, he tells Gemma and her work colleagues that it's his company's 25th anniversary party the following day and invites Gemma to attend. Thirty minutes later, M3GAN brings this party up as an opportunity to seduce Appleton and find AMELIA's kill switch. At the party itself, Gemma finds out that Cole has been recruited by Appleton, AMELIA seduces Appleton and steals all his information, and Gemma and Cole learn about it.
- Knives Out: Harlan Thrombey dies under suspicious circumstances shortly after his 85th birthday party. As private detective Benoit Blanc investigates, he asks Harlan's family to recollect the gathering and learns Harlan had several confrontations before the party started that may have inspired various suspects to murder him; but in flashbacks we see that one argument during the party was the one that began a chain of events leading to his death.
- Longlegs: In her first appearance, Ruby tells Lee that her birthday is coming up in a few days and invites Lee to the party. This becomes important halfway through, and is ultimately the setting for the ending.
- MaXXXine: Before her murder, Tabby announces that she's going to a party in the Hills, and Molly says the same when she and Maxine are talking outside her trailer. Maxine figures out just before the climax that all the victims are being lured to their deaths through the Hills parties and that she needs to go there to confront the killer.
- Nowhere: The characters spend much of the movie hyping up Jujyfruit's party, and overcome various obstacles to get there, notably Zero's car getting stolen by the Atari Gang. When they finally get there, it's quite the event, featuring Ducky trying to drown himself in the pool, Elvis beating Handjob to death with a soup can, and Mel committing to her promiscuous ways in a way that ticks off both Dark and Lucifer.
- The Rage: Carrie 2: The party after the big game where the massacre happens is mentioned several times near the beginning before Jesse invites Rachel. It's where she ultimately kills almost everyone.
- Saltburn: Early in his stay, Felix and Elspeth enthusiastically tell Oliver that they'll throw a party for his birthday near the end of the summer. This is what stops Felix from telling his family that Oliver was lying about everything, and where Oliver kills Felix.
- Sick: The "end of the world" party where Parker kissed Benji. We see it a couple of times through cell phone footage. Turns out it was a super spreader event and Benji died of COVID, which is the killers' motive for murder.
- Tangerine: A variant. Alexandra repeatedly says throughout the first half of the movie that she's performing at 7pm. Halfway through, it gets to 7pm and Sin-Dee has to swerve from her battle with Chester and takes Dinah to Alexandra's performance just in time.
- Beyond the Bitterroots: The hunting party Spoffard is organizing throughout the book is a ploy to use the other hunters as patsies to discover a dead body for him.
- Agatha Christie used this often.
- Two in Lord Edgware Dies: Two. The first is obvious, as Jane is at a party when her husband is murdered. Except in fact she isn't — Carlotta was, impersonating her. Donald Ross is killed when he figures it out... and that happens at another party. Donald overhears Jane mistake the "judgment of Paris" as referring to the city of Paris. This appears to be a simple social embarrassment, but it's much more significant to Donald because he was talking about culture with "Jane" at the dinner party. He puts these two parties together to figure out Jane had an impersonator — and so she killed him.
- Invoked and played with in Three Act Tragedy. Everyone assumes that Sir Charles's first party is this, where Babbington died, and that it holds the solution to the second party that ends in murder. But it doesn't — the first party is merely a trial run that serves to throw people off the scent. The second one is the important one.
- The Mirror Crack'd from Side to Side. Shortly before Heather was killed by a poisoned drink meant for Marina Gregg, she told Marina and Miss Marple about a previous time where she had snuck out while ill in order to meet Marina during another of her appearances. She infected Marina with German measles, which stunted the development her fetus and forced her to give the child up despite wanting him for years. This is why Marina killed Heather.
- Curtain: The drinks at the Franklins where Mrs Franklin was poisoned. Poirot realizes she was actually the murderer, and was trying to kill her husband. Hastings rotated the table while looking up a crossword answer, which caused a Poisoned Chalice Switcheroo.
- The Dresden Files: The third book features a ball being thrown for the paranormal community by the local Red Court nobility, as part of a trap for Dresden. Aside from setting up the book's climax, which triggers a War Arc that continues until the twelfth book, numerous other plot threads are planted which are still paying off years later.
- Eileen: Much hype is made and excitement is had by Eileen about Rebecca's Christmas party. It turns out not to be much of a party, and wasn't held at Rebecca's house at all - merely a front for revealing the crimes of Mrs. Polk, an incident which proceeds an Accidental Murder and Eileen leaving the town for good.
- A Good Girl's Guide to Murder: In both the book and the series, The Calamity parties only appear to be significant in that they're where Andie sold drugs. It's then revealed at the end that Max Hastings raped Becca at a 2019 Calamity party (using the drugs that Andie sold him), which was ultimately Becca's motive for killing Andie (albeit accidentally).
- Hit The Saddle: Craig misses Red Costain's trial (causing Red to get a lesser sentence without Craig's testimony) because he ran into another visiting New Yorker, Jim Paxon, who invited both Crai to a get-together at a get-together at his hunting lodge. On their way there, Paxon points out and says hi to a man he knew in Texas years ago. It turns out that Texan is now a killer living in town under a false identity and spends the first half of the book trying to kill Craig or run him out of town before Craig can learn that the man is using a different name than the one Craig met him under.
- It's mentioned several times in I Heard That Song Before that the night Grace drowned in the swimming pool she'd been hosting a small party at the Carrington mansion. It ended on a sour note because Grace got completely plastered even though she was in her third trimester of pregnancy; when Peter arrived home and saw this, he flew into a rage and publicly berated her. A few hours later, Grace was dead. When Greco questions the guests about their recollection of that night, several people mention that Grace had shown around a magazine article featuring her favourite actress; she later drunkenly tore the page out and still had it in her pocket when she drowned. It turns out that the photograph of the actress –- or rather the painting she's standing in front of –- is the key to the entire mystery and the reason Grace died, as it was proof the villain was stealing priceless artworks from the Carringtons to sell and replacing them with copies.
- Magpie Murders: The hunt for the gold piece at Pye Hall. Mentioned offhandedly, Mary Blakiston's other son Thomas drowned after finding the coin. But Atticus realizes that, because of the detail about Robert's wet trousers, that Robert actually killed Thomas in a fit of jealousy about finding the gold first. This caused Mary to write the letter implicating Robert that could be opened by Magnus in the event of her sudden death, which was why Robert had to kill him.
- A Song of Ice and Fire: In the first book, Ned Stark briefly recalls the Tourney at Harrenhal, a massive, multi-day tournament held by Lord Whent which took place when Ned was a teenager. Its significance is elaborated on in later books, including: Jaime Lannister's promotion to the Kingsguard, which ended his father's friendship with the king; Howland Reed befriending the Stark siblings; a mystery knight disrupting the joust before disappearing; Ashara Dayne apparently being dishonored; the possibility that the whole event was just a pretext for the great lords to conspire together against the king; and Prince Rhaegar snubbing his wife Princess Elia by crowning Lyanna Stark the Queen of Love and Beauty, which eventually lead to a civil war and the end of the Targaryen dynasty.
- Speak: We know that nobody will talk to Melinda since she called the cops on the end-of-year high school party. It takes almost a year for Melinda to reveal (and to acknowledge to herself) that she is selectively mute because she was raped by Andy there.
- Troubled Blood: The barbecue at Margaret Barnborough's house. It was mentioned as the only time C.B. Oakenden met Margaret, which caused him to write the tell-all book, and where Gloria vomited so much that she realized she was pregnant by her abusive boyfriend. But all of this is just a Red Herring for the ultimate reveal, which is that Janice, a Serial Killer, had poisoned the punch and caused Gloria's illness, privately hoping to poison them all. While it didn't work due to the bowl getting broken, Gloria's illness was enough to make Margaret suspicious, and so Janice killed her.
- While My Pretty One Sleeps: A few months back, Neeve invited Ethel to her annual Christmas party at her and Myles' apartment; Myles was annoyed that Ethel began nosing around Renata's cookbook and trying to cosy up to him when she realised he was a widower. Neeve, Jack and Myles all come to realise that Ethel had seen Renata's early designs for the Pacific Reef look in her cookbook, thus giving Ethel the first inkling that Renata was really the one who came up with the design.
- 13 Reasons Why: Several references to Jessica's birthday party are made throughout the series as some event Hannah attended before her suicide. Eventually, Hannah reveals in her tapes that Jessica had been raped by Jerk Jock, Bryce, at the party while Jessica was unconscious, and Hannah witnessed the event from inside a closet. We also learn that Jessica's boyfriend knew about this and let it happen. These events played a key role in why Hannah eventually took her own life.
- The ABC Murders (2018): Hermione mentions that Carmichael, her husband, always adored Poirot since they played a murder-mystery game at a party twenty years ago. This turns out to have been where the murderer, Franklin — Carmichael's brother — developed his obsession with Poirot.
- American Vandal:
- Nana's party in Season 1. Initially simply where Alex claimed (falsely) to have hooked up with Sara, it was actually where the spray paints had come from that drew the dicks, narrowing it down to someone who had been in attendance there.
- In Season 2, the skip day party that got broken up and got several people arrested. Tanner testified against Kevin because of thinking Kevin broke it up. He didn't, Lou did, trying to sabotage DeMarcus.
- Based on a True Story: Ava figures out midway through Season 2 that all the Copycat Killers' victims attended the same sex party, which prompts her and Nathan to go there in the following episode to find out more information. Though it's ultimately a Red Herring.
- The Beast in Me: Episode 3 opens with Nile looking at a party invitation for his two much younger half-brothers. Later, he invites Aggie to the party, which then acts as an opportunity for Abbott to scope out Nile's house and download the contents of his computer. The party itself is a Trauma Button for Aggie, who hasn't been around kids since Cooper died, and learns of Nina's association with Shelley.
- Elsbeth: The opening scene of ""An Ear for An Ear" is Vanessa at a dinner party with other surgeons, including Dr Y, and them putting their phones in a basket. That comes back around when it's revealed that Vanessa got hold of Dr Y's phone in that way later in the episode, sending the email that was her alibi.
- The Girlfriend: Daniel and Cherry's engagement party is mentioned at the beginning of the last episode. It becomes the setting for Cherry to be arrested for criminal damage at Laura's gallery, which ultimately breaks Daniel and Laura's bond permanently.
- I Love LA: The Formé dinner, which is implied to be a Met Gala Expy. It initially comes up in episode 6 when Maia meets her former boss, Ben, then Maia becomes obsessed with scoring it for Tallulah in episode 7, which culminates in her finding out Alyssa was trying to snub Tallulah, getting an invite for her, and getting fired. Episode 8 sees Maia and Tallulah decamp to New York for the occasion.
- Inside No. 9: In "Sardines"
, Geraldine mentions the last time Andrew's bedroom was open was when they had a scout jamboree twenty years ago. It's gradually revealed that this is where Andrew molested Pip, which is why Pip (in the guise of boring bank manager Ian) has returned in present day to get revenge on them.
- Mare of Easttown:
- In a case of Five-Second Foreshadowing, the family reunion is mentioned and seen on a T-shirt at the beginning of an episode. By the end of the episode, it's revealed that that is where Erin's relationship with Billy - or, actually, Erin's relationship with John - started, and how she got pregnant with DJ.
- The engagement party. The audience already knows that the Ross family were there, but it's revealed that that is where Ryan found out that John's affair with Erin was ongoing. John's calmness at the party is one clue that he was not actually Erin's killer, which helps Mare to figure out it was actually Ryan.
- Matlock: In "The Johnson Case", Linda Gallo's nephew threw her a 70th birthday party shortly before her murder. Olympia and her team believe that her nephew murdered her as they were heard arguing, but it turns out that she was actually murdered by a waiter who'd been hired to cater the event and was a convicted burglar.
- Pretty Little Liars: Original Sin:
- Last summer's bonfire party in the woods. It's mentioned a couple of times and Tabby has a few flashbacks to the fire in past episodes before it's revealed in "The Night He Came Home" that Tabby was raped there.
- Karen's birthday party. Initially introduced because it's where Karen and Imogen fought and Karen recorded the video, it's revealed to be where Imogen was drugged and raped, and that's how she got pregnant.
- Severance (2022): Harmony mentions early on that she's been invited to the Eagan family's gala. This is the setting of the finale, and Helly's outtie — Helena Eagan — is also in attendance, where innie Helly is woken up and manages to raise the alarm about severance.
- Veronica Mars:
- Shelley Pomeroy's party, which was always important as it was where Veronica had been raped, but whose true significance came back unexpectedly at the end of Season 2. While in Season 1, Veronica found out that she and Duncan had had consensual sex while drugged, Season 2 brought back Cassidy's story that he told her about being encouraged to rape her but not going through with it. In fact, he did rape her, and he infected her with chlamydia.
- The school trip that the kids were on when the bus blew up, to the Sharks stadium. It turns out later that Marcos and Peter had planned to reveal that Woody Goodman molested them, and that inspired Cassidy Casablancas to blow up the bus.
- The White Lotus (Season Three): The Full Moon Party, discussed by Chloe and Chelsea early in the season and happening on Gary/Greg's boat. The "day" portion in episode 5 provides the stressor for Tim to finish Victoria's pills. More prominently, the "night" portion in episode 6 leads to Lochlan kissing the high Saxon.
- Life is Strange:
- The Vortex Club party that happened just before the game begun. Kate is shown on video kissing multiple guys and very drunk. Max eventually figures out that she was spiked by Nathan, who took her to the Dark Room and took pictures of her.
- The Vortex Club party that Max sneaks into qualifies because Mr Jefferson is presenting the Everyday Heroes contest, which is how he manages to sneak up on Max after she and Chloe discover Rachel's body. But it qualifies even more so if you were nice to Victoria and she believes you that Nathan is dangerous — because, after he kidnaps Max, Mr Jefferson reveals that she came up to him at the party and told him about Nathan, causing him to kidnap and eventually kill her.
- Max Payne 3 opens with a fundraising party that gets attacked by gangsters. Nearly every notable character across the entire game makes an appearance in the level but Max is so out of it at the time he doesn't pick up on most of the payoffs.
- In the Sly 2: Band of Thieves level "A Starry Eyed Encounter", the MacGuffin that the Cooper Gang are after — the Clockwork Wings affixed to a statue — are being showcased in a party in Rajan's "ancestral palace." It is at this party that the other members of the Klaww Gang (The Contessa, Jean Bison and Arpeggio) make their first appearance and Sly dances with Carmelita in a Rhythm Game as a distraction, a photo of the event later used by Neyla to have Carmelita falsely arrested as a Cooper Gang member at the end of the following chapter.
- Pirates SMP: Near the end of the SMP, Ros hosts a Slumber Party at her Bright Castle, inviting her fellow Nightingale faction members — and later other server-members and NPCs — to attend. Not only does her castle get blown up and burnt down after the party is interrupted, but Ros also specifically mentions how Bek, Will, and Acho don't attend the party despite being invited — one of the few indications before it's revealed in the finale that the three have already been Killed Off for Real by the time the party takes place.
