 Voice actress June Foray (qv) was cast for both Karen and the  Teacher and had recorded vocals for both characters. However, only  her recordings for the Teacher made it into the final special as  another actress was called in to replace Forays Karen, for reasons  that even Foray herself to this day does not know. No changes were  made to the credits, so the actual voice actress we hear as Karen  remains unknown and uncredited. Forays Karen can be heard on the  Rhino Records soundtrack.