Singer-songwriter Paul Williams appeared in an episode where Felix's daughter Edna wanted to run away to follow Williams on tour. (Williams dissuades her.) Dick Clark made an appearance as himself, a radio disc jockey who calls Oscar in a contest, where he wins a new car ("The New Car", episode 76). Neil Simon (the author of the play which the series is based upon) makes an uncredited appearance in the fifth-season episode "Two on the Aisle", as does Bob Hope in The Hollywood Story.