Ilsa appears in the Casablanca episode of Sesame Street’s "Great Movie Classics". She is sitting in Rick's saloon listening to Sam serenade her on the piano. Recollecting the times she used to spend with Rick in Paris, she begs Sam to play the alphabet "for old time's sake", despite his trying to tell her that Rick has forbidden it. So he gives in. Then, when Rick comes in, Ilsa has time only to say a brief hello to him before leaving.
She is based on the character of the same name played by Ingrid Bergman in the 1943 classic film.