It's Always Sunny in Philadelphia is an American sitcom created by Rob McElhenney and developed with Glenn Howerton for FX. It premiered on August 4, 2005, and was moved to FXX beginning with the ninth season in 2013. It stars Charlie Day, Howerton, McElhenney, Kaitlin Olson, and Danny DeVito. The series follows the exploits of "The Gang", a group of narcissistic and sociopathic friends who run the Irish dive bar Paddy's Pub in South Philadelphia, Pennsylvania, but spend most of their free time drinking, scheming, arguing amongst themselves, and plotting elaborate cons against others, and at times each other, for personal benefit, financial gain, revenge, or simply due to boredom or inebriation.

Robert McElhenney III is an American actor, writer, producer, podcaster and businessman. He is best known for his role as Ronald "Mac" McDonald on the FX/FXX comedy series It's Always Sunny in Philadelphia (2005–present), a show he co-created with Charlie Day and Glenn Howerton and on which he continues to serve as an executive producer and writer. He is also known for playing Ian Grimm on the Apple TV+ comedy series Mythic Quest (2020–present), which he co-created with Day and Megan Ganz as executive producers.