Family Guy (2005)
Season 4, Episode 18
"The Father, the Son, and the Holy Fonz"
Context: Peter Griffin, the paterfamilias of Family Guy, secretly has his son Stewie baptized into the Catholic faith at the behest of his devout father. When Stewie becomes ill (due to "tainted" Holy Water), and Lois finds out about the deception, she encourages Peter to stand up to his father, and to exercise his agency in choosing his own belief system. Peter goes through a few religions before deciding to start his own religion that worships the graven image of Arthur Fonzerelli. One of his spiritual way stations happens to be Mormonism.
Exegesis: Family Guy seems to take pleasure in its casual blasphemy and sacrilege, and this particular episode is par for the course. It's frankly surprising that there haven't been more overt references to Mormonism in the series (although one cut-away gag in a later episode did involve the suggestion of incest between Donny and Marie Osmond...). South Park, another show that enjoys ridiculing organized religion and/or the people who belong to a given religion, have mentioned Mormons in a few episodes, basing one entire episode around denigrating the religion and casting fairly unkind, simplistic, and frankly untrue aspersions on our founding Prophet Joseph Smith. But Family Guy has only this one reference so far as I am aware, and they used it for a cheap polygamy gag.
Polygamy (or more specifically, polygyny) is a well to which comedy writers seem to return again and again. It appears to be the one detail that most people know about the Church of Jesus Christ of Latter-day Saints. It must be frustrating to comedy writers that the practice was abolished well over a century ago. But still, the idea of plural marriage is rife with comic potential (and dramatic potential too, apparently, viz.: Big Love). In a society where monogamy in marriage is the ideal (and ostensible norm, divorce rates notwithstanding), the idea of plural marriage seems utterly alien. And anything alien can easily be tweaked for the sake of a laugh. It's glaring "otherness" is likely the reason why it remains the most salient detail people remember about Mormons.
I don't find polygamy jokes inherently unfunny. This one wasn't particularly clever, though Family Guy's fans don't seem to be the most discerning comedy connoisseurs. (Full disclosure: there isn't an episode of Family Guy that I haven't seen.) Polygamy jokes constitute a great deal of the incidental references to Mormons and Mormonism in pop culture, and some are funnier than others. The Church has gone to great lengths to distance itself from the practice of polygamy, but are stymied by the kooks who continue to practice it (who regrettably are referred to as "Mormon Fundamentalists", even if not all of them self-identify as such). One would think it would be easier to distance ourselves from a practice that was hardly defining; it was only practiced by a comparatively small subset of Church members, for a short period if time, over a century ago. (The fact that religious precedent exists for the practice throughout the Old Testament doesn't seem to make the practice any more defensible or less bizarre to most people.)
Due in part to depictions of Mormons as polygamous in this and other shows, the misleading Mormon/Polygamy association will likely, unfortunately, continue into the future.
And, of course, when Peter's "Mormon" wives point out (correctly) that Mormons don't drink alcohol, Peter promptly throws them away, literally, in garbage cans. I'm not sure how to begin an exegesis of that...