The phrase "pivotal scene" refers to a significant and crucial moment within a story, play, or movie that dramatically impacts the outcome or understanding of the plot. Full definition
Without a moving score, there would be nothing to help drive emotion in the most pivotal scenes where we are witnessing nothing except a sheet. (digitalchumps.com)
Particularly in a certain, highly pivotal scene near the end of the game. (riddlethos.com)
In the shadow of the old home was a dance floor where the filming of one of the story's most pivotal scenes was taking place. (screenrant.com)