Reign Fall - Episode 10:

If you meant the TV show , Season 2, Episode 10 ("Mercy") is the iconic "fall finale" where Francis confesses to regicide to Mary, forever altering the course of their marriage and the French throne. Review: NCISLA “Reign Fall” (S6E10) - wikiDeeks

We see Sam’s calm, calculated approach to pressure, providing a sharp contrast to Deeks’ simmering rage. Episode 10: Reign Fall

The title most famously refers to Episode 10 of Season 6 of the police procedural NCIS: Los Angeles . However, if you're looking for the CW historical drama Reign , its mid-season "fall finales" or Episode 10s often carry similar themes of power collapsing. If you meant the TV show , Season