Born in Philadelphia Rob McElhenney is mostly known for his role as Mac on the show It's always sunny in Philadelphia. Rob is also creator, writer and director of the show. Rob struggled for many years trying to make a living as an actor. He spent 8 years working in New York doing all kinds of acting jobs, including a guest appearance on Law & Order. He is currently living in Los Angeles and has been engaged to It's Always Sunny In Philadelphia Co-star Kaitlin Olson since December 2007.