Parties are a fun sort of gathering. Really fun. However, sometimes parties can lead to bad things happening and we don't mean the kind where someone drives a car into the pool or hangs off the chandelier. Usually, parties usually end with the hero getting called out for something they did before, such as, say, ditching their friends for the party in the first place. Or maybe a secret is revealed, like a secret affair. Whatever the case, it always kills the mood of the party and ultimately brings the work to a, albeit brief, dramatic moment. Hence the nod to Cerebus Syndrome. In order for this trope to work, one of the things that has to happen is something bad happening at the party that drags the mood into downer levels. These scenes usually happen right before the third act, so beware of spoilers. Compare Nasty Party, when the party is just a front for the host to murder everyone.
- The Room has Johnny's birthday, in which the affair between Lisa and Mark is revealed. Unlike other examples, it got worse from there on.
- Bedtime Stories has Skeeter getting fired from his job at a Tiki party in an attempt not to get himself burned alive.
- Alvin And The Chipmunks The Squeakquel has Alvin choosing (accidently) the football game over his performance at the concert, which results in the Chipettes winning by default and causing his brothers to ignore him when he returns home with a bunch of regrets after being called out by Brittany.
- Edgar Allan Poe's The Masque of the Red Death has this as the ultimate result for Prince Prospero and his guests, when a red-clad stranger decides to crash their big party.
- Subverted in Thirteen Reasons Why, where the narrator keeps talking about a party he and Hannah both went to as if it were ominous and the final straw for her before she committed suicide, but really the party was just one reason and not one of the biggest (Hannah even says at the beginning of that tape that the person involved didn't even deserve to be on her list). The final straw was something much more subtle.
- East Enders is renowned for being cursed to tragedy whenever a party occurs, usually resulting in a death, family disaster or shocking revelation. Alistair McGowan's Big Impression made a sketch revolved around Lampshading this.
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