Dallas S14E22 - Conundrum

In this two-part episode, J.R. is on the brink of despair, holding a gun to his own head, when he's visited by an other-worldly type named Adam. He takes a mystical journey in the "It's a Wonderful Life" slant and finds out what the lives of those around him would have been like had there never been a J.R. Ewing. What he sees is a world where Gary Ewing is a successful lawyer, Cliff Barnes is vice-president of the United States, Cally Harper is a battered wife, Bobby Ewing is a wandering loser, Sue Ellen Shepard is a thriving actress, and the other Ewing son is named Jason -- and is a weasley little user and jerk. Finally, the two-parts -- and the series -- ends with a gunshot.