J.R. Ewing is a fictional character from the American television series Dallas, which aired from 1978 to 1991. He is portrayed by actor Larry Hagman and is known for being a ruthless oil tycoon and the primary antagonist of the series. J.R. is characterized by his cunning business tactics, manipulative personality, and complex relationships with his family, particularly his brother Bobby Ewing. The character became iconic for his memorable catchphrases and schemes, often involving betrayal and power struggles within the Ewing family. J.R. Ewing's influence on popular culture is significant, making him one of television's most recognizable villains. His character's legacy continues to be referenced in various media.