It's Always Sunny in Philadelphia(2005)

Five people run a Philadelphia bar badly, scheme constantly, and suffer consequences they never learn from. That loop, repeated across seventeen seasons, is the whole premise and the whole joke, and it holds up because the characters' self-regard is so total and so misplaced that each new disaster feels freshly earned.

Episodes land independently of each other, so there is no continuity debt and no emotional throughline to track. The humor stays abrasive throughout: no warmth creeps in, no one softens, and the group's friendship functions more as mutual enabling than affection. That refusal to grow is what keeps the tone consistent from the earliest seasons to the most recent.