Due to the violence portrayed in the Cowboy Bebop world and violence in Japanese schools, the series was briefly cancelled and an extra session was created as a final episode to the first thirteen episodes aired. Called "Session XX: Mish-Mash Blues," a compilation of clips from previous episodes, it aired on June 26, 1998 on TV Tokyo. The episode was never released on DVD. In it, the characters provide a philosophical commentary and end with the words: This Is Not The End. You Will See The Real "Cowboy Bebop" Someday!
[Source: AniDB]