In this movie, they appeared, at least as harmonies, in just about every song, except perhaps "Mean Green Mother from Outerspace". It is questionable whether they are really there, meaning when characters can see them. the only time it is 100% confirmed they are there is when they appear as street urchins, warning Audrey that Orin Scrivello, D.D.S is wrong for her. During the song Suppertime, it appears that they are telling Seymour to get Mushnik to go inside of the Audrey II plant. This adds a bit more to their characters and their intentions.
Crystal is played by Tichina Arnold, Ronnette is played by Michelle Weeks and Chiffon is played by Tisha Campbell; all of whom lent their singing talents to the roles.
Both Tichina Arnold and Tisha Campbell starred in the sitcom Everybody Hates Chris.