It's Always Sunny in Philadelphia is an American television sitcom created by Rob McElhenney and developed by McElhenney, Glenn Howerton, and Charlie Day. It premiered on FX on August 4, 2005. The show follows the exploits of a group of friends who run Paddy's Pub, an unsuccessful Irish bar in South Philadelphia. Each character can be described as very dishonest and antagonistic. These include Glenn Howerton as Dennis R. Reynolds, Kaitlin Olson as Deandra 'Sweet Dee' Reynolds, Charlie Day as Charlie Kelly, Rob McElhenney as Mac, and Danny DeVito as Frank Reynolds.