Bill Lawrence revealed that Neil Flynn improvised many of his lines as the Janitor on the sitcom Scrubs. The writer credited Flynn's comedic talent during moments when the script lacked specific dialogue.
Lawrence explained in a 2018 interview that scripts sometimes directed Flynn to simply say something funny when a Janitor line was needed. One notable example came in the Season 8 episode My Lawyer's in Love, where Flynn improvised a story about a topless fistfight with a duck alongside the road.