The pair mainly appeared in season four's "Krusty Gets Kancelled" but they also appeared in "Bart to the Future", "Homerazzi", "All About Lisa" and The Simpsons Movie.
(See The Great Gabbo.) Artie Ziff is a narcissistic Internet entrepreneur who is infatuated with Marge Simpson, his former high school classmate.
A number of them have gained expanded roles and have subsequently starred in their own episodes.
According to the creator of The Simpsons, Matt Groening, the show adopted the concept of a large supporting cast from the Canadian sketch comedy show Second City Television.
He is voiced by Jon Lovitz, except for a brief appearance in "The Front" (1993), in which he was voiced by Dan Castellaneta.
The writers originally intended many of these characters as one-time jokes or for fulfilling needed functions in the town.
However, this would contradict the earlier episode when it is revealed that Seymour is not her birth son.
In "Grade School Confidential", it is revealed that Agnes enjoys collecting pictures of cakes that she cuts out of magazines, a hobby she began in 1941. In the twenty sixth season episode "Sky Police" she mentions that she has a brother Stevie.
The show is a huge hit that ruins Krusty's career, but Bart then ruins Gabbo's future by capturing him making a rude comment on TV.
The pair are later reduced to low-paying work such as a show at an Indian casino.