One of my favourite film/television clichés would have to be the elevator breakup/goodbye. Nothing severs a relationship like the finality of an elevator door sliding shut. It’s like a visual razor-blade or slow moving sideways guillotine.
Many factors have to line up for this to be effective.
First: The couple must be alone on the elevator. (Mind you; a third person could be great, especially if they are not revealed to be on the elevator until the end of the scene.)
Second: One member has to get off on a different floor than the other. Logistically, in the real world most couples (when riding in elevators) are heading to the same destination unless of course they both work in a hospital where multiple floor scenarios are a common occurrence.
Third: The final speech must be timed perfectly to end just as the elevator door closes. Enough time must be allotted for one last meaningful glance into each other’s eyes. Luckily, the elevator door will somehow sense this and close at the appropriate moment.
Makes me smile every time.