Today in 1980 was a watershed day in the history of television. An estimated 350 million people tuned into Dallas around the world, to find out "who shot J.R." J.R. Ewing, one of the principal characters on the show, had been shot in the final episode of the season that ended the previous March. It was an infamous cliffhanger.
The twist ending left America gasping for answers. "Who shot J.R." became a mantra for eight months. On November 21, 1980, it was revealed to the world that Kristin Shepard, J.R.'s former mistress and sister of his wife, was the one who pulled the trigger.
Dallas debuted in 1978 and ran for twelve full-length seasons after its initial five-episode pilot season. It was the first "primetime soap opera," involving plot threads that spanned multiple episodes and racy themes. It was a precursor of what is now standard operating procedure in TV writing.
The show followed the trials and travails of two Texas oil families - the Ewings and the Barnes. Jock Ewing and Digger Barnes, heads of their respective families, were former partners engaged in an ongoing feud over oil rights. The warring dynasties are bound by the marriage of Barnes's daughter Pam to Ewing's son Bobby.
J.R. Ewing, the eldest Ewing son, was played by Larry Hagman. The villainous J.R. inspired disgust in the show's viewers for his philandering and greedy habits. He had made so many enemies on the show by the time he was murdered, speculation ran rampant as to who was the actual culprit.
The episode that revealed it was Kristin Shepard was one of the most watched episodes of television in history. The domestic audience was eighty-three million people. That means about 76% of all American televisions turned on that night were tuned to Dallas.
The cultural phenomenon of "Who shot J.R," a popular t-shirt slogan, led TV writers to implement cliffhangers as a stock trade trick.
Perhaps an even bigger shock than J.R.'s murder was the infamous copout in September of 1986 when an entire season was revealed to be one of Pam's dreams.
The show's final season aired on May 3, 1991. Knots Landing, a spinoff, ran from 1979 to 1993. Dallas is still in global syndication.