3. The Nightman Cometh
In the world of scheduled television, the fad of the musical episode has been floating around for a while. Some shows do a great job at is (like Scrubs or Community) while other shows don't work as well (we mean you, Grey's Anatomy). But when it was time for It's Always Sunny to try and incorporate music into an episode, they took a different approach. They had an entire episode about Charlie's musical, The Nightman Cometh, which The Gang (along with help from others) performed. It is revealed at the end of the episode that the point of the musical was to woo The Waitress, which obviously doesn't work. The musical itself worked pretty damn well, though! The Gang went on to tour the country and do live renditions of The Nightman Cometh, which included extra songs and Danny DeVito's then wife, Rhea Perlman, on the piano. Not only is this episode one of the best episodes of the series, they managed to take it to a whole new level.