Eternal Family (1997)

Champon City's top-rated TV show is Eternal Family, a dramatic comedy about the dysfunctional Hanada family and their daily shenanigans: the normal patriarch Ben, his constipated wife Ako, their unhinged daughters Akiko and Sae, their violent sons Sasuke and Michael, and their pet dog and chicken. But a bizarre secret lies behind the family: everyone is actually unrelated but has been brainwashed into thinking they are (as part of a sociological experiment that went haywire but ironically became a commercial success), and Ben is the only one who knows the truth and they are being televised. This strange clan has spent their whole life within the confines of their home, under the watchful eyes of the studio personnel that have imprisoned them. But when a plumbing disaster sets them free and into the real world for the first time ever, the Eternal Family is unleashed on the unprepared residents of Champon!