'Soap'

In 1977, this prime-time quasi-comedy became the first show to realize what movie serials and afternoon soap operas had known for years: Cliffhangers suck in viewers. Two years before J.R. Ewing would take a more-publicized bullet, Robert Urich's philandering tennis pro got shot on "Soap." Technically, the move was supposed to be spoofing cliffhangers -- but instead, it brought them into the mainstream once and for all. Much like the program's trailblazing plotlines concerning gay parenting, impotence, interracial marriage and other such topics, "Soap" was once again ahead of the game.

'Dallas'

A quarter-century later, you still can't say the word "cliffhanger"
without thinking about J.R. Ewing -- and, well, possibly Sylvester
Stallone. But it was the "Who Shot J.R.?" end to Season 2 that made the concept a reliable TV tool for future talents (J.J. Abrams, who was 14-years-old at the time, was undoubtedly watching). After infuriating every living being in the Lone Star State, oil tycoon J.R. (Larry Hagman) was confronted by a mysterious assailant who had appeared in his office. After the shot rang out, audiences speculated for eight months -- and Hagman took off for Europe, refusing to show up for filming until the suddenly dependent program renegotiated his contract. After a media frenzy that included the covers of Time and People -- and launch fodder for an ambitious network called CNN -- Ewing's killer was finally revealed Nov. 21, 1980, to be his sister-in-law/jilted mistress Kristin. An astounding 76 percent of all U.S. television viewers watched that night.

'The Simpsons'

Much like "Soap" invented the prime-time cliffhanger by spoofing the daytime gimmick, and "Dallas" took things to the next level by ripping off "Soap," "The Simpsons" launched a bona fide phenomenon when the show's creators set out to make a parody of the "Who Shot J.R.?" phenomenon. Once again, the wealthiest man in town, in this case -- the odious Mr. Burns, single-handedly ticked off everyone around him, then found himself at the bad end of a bullet. As the summer months of 1995 passed, audiences found themselves pondering Apu's shifty eyes, Lisa's propensity for environmental extremism and, of course, Smithers' possible motive as a jilted lover. The two-part episode turned out to be one of the most popular adventures of Springfield's yellow family ever, and it sure did prove convenient that the would-be assassin (Maggie) was too young to be held accountable.

'Green Wing'

OK, it's a little obscure on these shores, but credit must be given for quite possibly the most literal interpretation of the word "cliffhanger" to ever air. This critically acclaimed British medical comedy found the inspiration at the end of its initial nine-episode run to take central characters Guy, Mac and Martin and put them all in an ambulance. The distraught Guy, driving erratically, slams the breaks and ends up with the ambulance literally dangling over the side of a cliff. End of series. In a later, second group of episodes, the show's creators once again hung the fate of characters over the edge of a cliff. Why can't American comedy be this clever?