I won't rehash what everyone else has written, as by now everyone knows the premise, characters, and significance of this classic pop-culture institution. But do want to discuss "All In The Family"'s groundbreaking synthesis of razor-sharp contemporary comedy and hard-hitting, sometimes heartbreaking drama--a Norman Lear specialty, as it turned out. The series as a whole could reasonably be considered the origin of the infamous "Very Special Episode" phenomenon of a decade later but no other series ever rode that fine tightrope as successfully...some of those attempts were incredibly cringe worthy (which as an '80s child I remember all too well, and wish I didn't!). When the show would shift gears into Serious Mode the effect could be very uncomfortable, and as I recall the scales tipped more and more in that direction in later seasons, but it never seemed gratuitous or grotesque as, say, dramatic episodes of "Diff'rent Strokes" (or any episode of "House Of Payne"). This was a show that routinely dealt with hot-button subjects, the onscreen tension was always high, and often the only thing separating a laugh from a gasp of horror was the presence or absence of an Archie malapropism, a smug put-down from Meathead, or a dingbat remark from Edith. If I remember correctly they even managed to get a small, nervous giggle from a horrified audience watching a man attempting to rape Edith. The eruptive cheering as she escapes her attacker is testament to the powerful writing this crew was capable of, when they weren't thinking up zingers for Archie and Mike to bat around.
The show's writers and cast were smart, maybe too smart for a sitcom. They realized that the best comedy arises from drama and vice versa in a graceful dance; you can't just stick a serious story into an otherwise lighthearted or buffoonish series without giving the audience emotional whiplash. Many sitcoms have tried, few have succeeded, and I'd argue (with "M*A*S*H*" being a close second) that none has ever nailed the formula like the one that started it all.
The show's writers and cast were smart, maybe too smart for a sitcom. They realized that the best comedy arises from drama and vice versa in a graceful dance; you can't just stick a serious story into an otherwise lighthearted or buffoonish series without giving the audience emotional whiplash. Many sitcoms have tried, few have succeeded, and I'd argue (with "M*A*S*H*" being a close second) that none has ever nailed the formula like the one that started it all.