It's Always Sunny in Philadelphia
The first season ran for seven episodes with the season finale airing September 13, 2005. According to McElhenney, word of mouth on the show was that it was good enough for FX to renew it for a second, which ran from June 29 to August 17, 2006. To boost ratings and achieve more mainstream exposure, Danny DeVito joined the cast in the first episode of the second season, playing the father of Dennis (played by Glenn Howerton) and Dee (played by Kaitlin Olson). Reruns of edited first season episodes began airing on FX's parent network, Fox, in 2006. On August 18, 2007, a preview episode from a third season episode "Mac is a Serial Killer" appeared on the group's MySpace page. The third season ran from September 13, 2007 to November 15, 2007. On March 5, 2008, FX renewed It's Always Sunny in Philadelphia for a fourth season. On July 15, 2008, it was reported that FX has ordered 39 additional episodes of the series which means that the show will run until at least a seventh season. All remaining seasons will consist of 13 episodes. All five main cast members were secured for the entire scheduled run. The fifth season ran from September 17, 2009 to December 10, 2009.[4] On May 31, 2010, Comedy Central began airing reruns of It’s Always Sunny in Philadelphia.