25 Best 'It's Always Sunny in Philadelphia' Episodes, Ranked According to IMDb

It's Always Sunny in Philadelphia (IASIP) first premiered on FX in 2005, and with its 16th season, it has become the longest-running live-action sitcom ever – and with another two already ordered, it's unlikely to end anytime soon. It stars Charlie Day, Glenn Howerton, Rob McElhenney, Kaitlin Olson, and Danny DeVito as egotistical friends often described as "the worst people in the world" who own the unsuccessful Paddy's Pub in Philly.