Day: I said, "Let me go off and write some of the songs and lyrics," and I went to the piano. We'd already had the Dayman song, so I pulled out the "Troll Toll" and "Tiny Boy, Little Boy" songs.

Olson: I spent months waking up in the middle of the night singing "Tiny Boy, Little Boy."

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

Day: I contacted David Hornsby, a writer who plays Rickety Cricket on the show. I got on the piano and plucked out some songs, and we kind of made up what the characters are singing and doing as we went along. I sent them to Cormac Bluestone and asked if he could help me do some arrangements for the songs.

Matt Shakman (director): "The Nightman" was part of Fred Savage's block of episodes to direct that year. Because they were still tinkering with it, they ended up moving it into my block—to my great fortune.

Howerton: We spent days rehearsing the musical before we ever shot anything, rehearsing the music so that we had all the songs and all the staging down.

Shakman: We rehearsed on weekends and then took a full day off in the middle of our shoot schedule—which is kind of unheard of in television—and just worked on how you would rehearse the play.

Day: It wasn't really the most hilarious episode to film. It was pretty technical.

Shakman: I wanted it to exist as a full theater piece, so I brought in 100 background performers who had no idea what they were about to watch and told the guys, "Just do it all the way through." I got Artemis [Pebdani] to act like the stage manager of the event and actually come out and do the speech that you always hear in shows about where the fire exits are.

McElhenney: The audience didn't have any context, so I remember a lot of confused faces as we were performing. People [who weren't familiar with the show] were wondering why it was funny… But I always go back to Glenn and Charlie; if they're still laughing, then I know it's funny.

As part of Charlie's elaborate marriage-proposal scheme, he brings in a woman named Gladys at the last minute to perform the show's music. Mae LaBorde, who was 99 at the time, played the role.

Olson: She was the best. She really enjoyed having some people to talk to, so she took advantage of it.

Howerton: She just started improvising all this shit. Some of the outtakes are unreal.

DeVito: She was very, very funny. She was an old character-actor lady; she was really good.

McElhenney: She was so sweet. We would give her a line and she would say it, and then she would just keep going and going and going.

Day: They would say "action" and she was just, like, talking. She would tell us that we're all wonderful, beautiful people and she was happy to be there. Which was really charming but also very funny, because she had lines and she wasn't saying them.

Shakman: When you get to be as old as she was, you can do whatever you want… Just getting the lines out was very difficult. I remember being backstage with her, talking about Calvin Coolidge, she just went on for so long. It might've been the longest scene I've ever shot for Sunny.