Scènes à faire

Scènes à faire (French for "scenes to be made" or "scenes that must be done") are the scenes or scene elements that a fan of the genre in question expects to see in a work set in the genre, or in a particular location. You can't tell a story in this genre or this setting without them.

They're a step up from a genre's Necessary Tropes, in that they're elements that take place to establish or further the story to a greater or lesser extent. They usually contain tropes of their own.

Tropes Are Not Legos, and scènes à faire are not legos, either. They have to be customized to fit the story that they're used in.

Scènes à faire don't count as copyright violations per se - while they are expressions of ideas that other people have written down in the past, they're necessary elements in a story. The first person to use them was original; everyone who follows in their footsteps is writing what they need to write in order to tell a story in the same genre or setting. For example, we'll quote from The Other Wiki:

The United States Court of Appeals for the Second Circuit interpreted the scènes à faire doctrine expansively to hold that a motion picture about the South Bronx would need to feature drunks, prostitutes, vermin, and derelict cars to be perceived as realistic, and therefore a later film that duplicated these features of an earlier film did not infringe.

Contrast with The Stations of the Canon, where a Fan Work has its own spin on specific scenes that were in the original work.

Examples of Scènes à faire include:

Your action-adventure private detective will likely end up in Hot Pursuit of a suspect, possibly starting with a cry of Follow That Car! or involving a Sheet of Glass along the way. Depending on how far into the story the scene takes place, the detective might or might not catch the suspect - odds of apprehension are inversely proportionate to the length of story remaining.
When - not if - the climactic ship-to-ship battle takes place in the days of Wooden Ships and Iron Men, the characters will board and storm their enemy's ship.
In Japanese mystery works, the Engineered Public Confession takes place at the edge of a cliff overlooking the sea.
Superspies use concealed gadgets, visit exotic locations, meet femmes fatale and love interests (sometimes the same person) and get into Chase Scenes while carrying out their missions - which often result in Saving the World.

And the examples we have need sorting by genre, too.