How It's Always Sunny In Philadelphia's Dayman Became The TV Masterpiece We See Today

The musical episode of "It's Always Sunny in Philadelphia" came from a pretty unexpected place. Widely regarded as one of the best episodes of the 16-season sitcom, "The Nightman Cometh" was such a hit the gang even performed the show live. The musical's unforgettable original songs were written over several stages, but the one that inspired the rest was "Dayman," the hero's theme, which was actually written for a different episode.

Charlie Day's character is the one to conceive of the musical on the show, and the actor was also the force behind the episode in real life. He was always interested in making a musical episode of the series, but his co-creators felt that they couldn't just make a musical for no reason — the character needed a clear motivation for writing and producing something of such great effort. No one on this show does anything without ulterior motives, and everything is a scheme. This spawned the question — who is this musical "versus?"

"It became a running joke in the script because they're constantly asking, 'Why did you write a musical?'" Day recalled in an interview with GQ. "And my character says, 'Just for fun,' and someone says, 'No one just does it for fun. Who are you trying to beat?' [...] It went back and forth, back and forth, so we landed in both areas. Yes, the characters all just do a musical. You don't find out until the end that this is just a really pathetic marriage proposal."

As for why the other characters join his cast, the writers quickly discovered that their rampant narcissism was reason enough. "We finally realized: Maybe Charlie writes the musical and our characters are just so f***ing vain that we can't stomach the thought of Charlie getting other people to do it," co-creator and star Glenn Howerton said.

The songs for "The Nightman Cometh" came mostly from Day, as his collaborators will attest, although some of the hilarious lyrics were spawned in the writers' room.

"I'm not musically inclined in any way, shape, or form," added Rob McElhenney, co-creator and star. "But Charlie is an incredible musician, so he and [composer] Cormac Bluestone wrote the majority of the music. In terms of lyrics, we all had a hand in them. But Charlie definitely took the lead."

Once Day was given the reigns, he was happy to take over — with Bluestone's help, of course. "I said, 'Let me go off and write some of the songs and lyrics, and I went to the piano," he continued. "We'd already had the Dayman song, so I pulled out the 'Troll Toll' and 'Tiny Boy, Little Boy' songs."

This begs the question — where did the Dayman song come from? This song actually predates the musical episode entirely and originally sprang from a totally different storyline — a glam rock band from season 3.

"We knew we wanted to have an episode about a band," McElhenney told Entertainment Weekly. "So we started questioning, 'What is the kind of the music that this band plays?' The lyrics were written by a couple of our writers, as well as Charlie, to create 'Day Man, fighter of the Night Man, champion of the sun, master of karate and friendship for everyone.' And then the music was Charlie and Glenn Howerton and another buddy of ours, David Hornsby, who plays Rickety Cricket. He had the suggestion of putting in the voice from Flash Gordon. It goes, 'Flash... Ah-ahhhhhh!' That's where Dennis [Howerton] got, "Day Man... Ah-ahhhhhh!"

The song made its way into this season 3 episode only to be repurposed later for the musical.

"Dayman" was the brainchild of the "Sunny" creators and cast, but Day was the undisputed musical force behind "The Nightman Cometh."  He also had some help from Bluestone, a long-time friend. The composer assisted Day with the arrangement, although the comedian already had "loose versions of some of the songs," as he explained on The Always Sunny Podcast. 

Bluestone helped arrange these ideas and "mash[ed] them together]" with his own. The composer was impressed with Day's musical vision "[Day] had really strong ideas," Bluestone confirmed. "Like, I listen to them, and I'm like, this was all Charlie. Like, little boy, tiny boy, little boy, you were like 'Oh, it's gotta be Sondheim-y.'"

Even though he chose a comedic path in life, Day had always secretly wanted to write a musical. He used his comedy series as a vehicle to do so, but this approach also protected him from the criticism that often accompanies musicals.

"The beauty of what we're doing is you have an absolute bail-out parachute of a joke, which means we don't have to do anything in earnest," the "Fool's Paradise" director continued. "Which means that we can fall right flat on our face. Like yeah sure there's a piece of me that's always like I wanna write a musical, that'd be fun. I don't have the guts and balls to actually write a musical and put it in front of the world, then I'm safe, right? And kind of our show is such a good sandbox, like, playground for trying things. Just like, I'd like to write a David Bowie-esque rock song, I can do it on our show. Or like, I'd like to try an English accent, but it can be bad."

The glam rock origins of the "Dayman" theme made their way into the musical in unexpected ways. Just like in the season 3 band episode, Dennis and Mac are both wearing harsh and distinctive stage makeup akin to David Bowie. Makeup wasn't the only thing that reminded fans of Ziggy Stardust. Mac's accent also sparked a particular Bowie memory for one super-fan — "Hamilton" creator Lin Manuel Miranda. 

"Your accent as the Nightman, it's very David Bowie in 'Labyrinth' to me," Miranda told McElhenney on the "Sunny" podcast. "There's something quiet about it that's very David Bowie as Jareth."

That original song was so catchy that it inspired a whole musical, but every other song in the catalog was equally unforgettable for the fans and the cast alike. "I spent months waking up in the middle of the night singing 'Tiny Boy, Little Boy,'" Kaitlin Olson, who plays Sweet Dee, told GQ.

"I never stopped singing, 'You gotta pay the troll toll to get into that boy's hole,'" DeVito added. "After that episode, wherever I'd go, people would scream it [at me] out of windows."

"The Nightman Cometh" might have been Day's baby, but the final product was a collaborative effort from everyone involved with "Sunny." The rest of the cast probably never imagined that the silly song from season 3 would spawn an entire theatrical production, but that's the magic of Paddy's Pub for you!