Nightman

"The Nightman Cometh" is the thirteenth and final episode of the fourth season of the American sitcom television series It's Always Sunny in Philadelphia. It is the 45th overall episode of the series and was written by co-creators Charlie Day, Glenn Howerton, and Rob McElhenney and directed by producer Matt Shakman. It originally aired on FX on November 20, 2008. In the episode, the Gang performs a rock opera based on songs written by Charlie, unaware of his true motives for spontaneously putting on the production. Since its original broadcast The Nightman Cometh is widely regarded as one of the best and "classic" episodes of the series. It was later adapted into a short-lived stage musical in 2009, with the series' cast reprising their roles.