It's Always Sunny in Philadelphia Season 15 full movie online on FMovies. In season fifteen, the gang finds themselves at a crossroads in this strange new world in the wake of Covid-19 and all things 2020. The rules are changing quicker than anyone can keep up with, despite herculean efforts from Mac, Charlie, Dennis, Dee, and Frank to continue business as usual. They must also now face the music and decide who they’ll become in the cultural upheaval that is 2021.