35 years ago, the Texas oil baron J.R. Ewing was working late at his office when he was shot twice by a mysterious assailant. J.R. crumpled to the ground with his fate unknown, and every member of the cast a plausible suspect in the shooting. With that, the third season of CBS’s Dallas concluded, but at the same time, it also graduated from hit network show to nationwide phenomenon.
The end-of-season cliffhanger, deployed so effectively in 1980 that “Who Shot J.R.?” became a national catchphrase, is a brilliant and oft-used television device. But in a fractured TV landscape that no longer takes the summer off, it's a ploy that struggles to punch with the weight it once did. Dallas aired during the golden era of the “big three” TV networks, when there was no way to binge-watch and catch up with the hit of the moment. So its third season finale was an innovative gambit—the cliffhanger was the stuff of serialized soaps and Charles Dickens, not the world of episodic television, where mysteries were tidily solved every week.
"Who Shot J.R.?" was hokey and not particularly compelling from a writing standpoint—almost every character on the show had a reason to shoot the manipulative and unscrupulous patriarch, so it was almost beside the point when Dallas revealed who actually did it eight months later. But it was the kind of water-cooler moment that could drive conversation about the show during the quiet summer months of the network TV schedule. Dallas was serialized television, but not so much that viewers couldn't jump right into any given episode and figure it out, and after a few months of hearing co-workers or family members debate their theories about potential suspects, it was hard not to. The show ended its third season as the sixth-most watched show on television, with 19.1 million viewers; its fourth season jumped to number one, with 27.6 million people watching. The reason for that kind of meteoric leap in ratings is indisputable.