J.R. is a fictional character from the television series Dallas, which aired from 1978 to 1991. He is portrayed by actor Larry Hagman and is known for being a cunning and manipulative oil tycoon. J.R. is often seen scheming against his rivals and even his own family, making him one of the most memorable villains in television history. The character became iconic for his catchphrase, "Who shot J.R.?" which refers to a major plot twist in the show's third season. This storyline captivated audiences and led to a significant increase in viewership, making it a cultural phenomenon during the late 20th century.