Simon & Marcy "everyone [working on the series] was pitching in to make this one special". The episode features the voice of Ava Acres, who portrays the young version of Marceline. Acres had previously appeared in the third season episode "Memory of a Memory". As mentioned above, the episode makes notable use of the 1982 song "Where Everybody Knows Your Name" by Gary Portnoy—better known as the theme to the sitcom "Cheers". According to Sugar's father, Rob, on his official YouTube channel, the use of the song started merely as a placeholder. However, as the episode developed, Sugar decided to keep it in
Where Everybody Knows Your Name of "TV Guide" magazine named "Where Everybody Knows Your Name" the greatest TV Theme of all time. In the episode "Simon and Marcy" in the animated series "Adventure Time", the Ice King sings the song to himself to maintain his sanity as he wears the crown responsible for his power. He also acted out scenes of the series of the theme song in the episode to cheer up his charge, Marceline. The web series "How It Should Have Ended" parodies the theme song in the intro to their "Villain Pub series". The song appears in a 2017 TV commercial for