"Who shot J.R.?" is an advertising catchphrase that American network CBS created in 1980 to promote the television series Dallas. It referred to the mystery surrounding a murder attempt against the character J.R. Ewing in "A House Divided", the show's third-season finale. The mystery was not resolved until the fourth episode of the fourth season, "Who Done It", which aired eight months later.
In the final scene of the 1979–80 season, J.R. Ewing (Larry Hagman) hears a noise outside his office, walks out to the corridor to look, and is shot twice by an unseen assailant. The episode, titled "A House Divided", was broadcast on March 21, 1980, and was written by Rena Down and directed by Leonard Katzman. Viewers had to wait all summer to learn whether J.R. would survive, and which of his many enemies was responsible.
Ultimately, the person who pulled the trigger was revealed to be Kristin Shepard (Mary Crosby) in the "Who Done It?" episode which aired on November 21, 1980. Kristin was J.R.'s scheming sister-in-law and mistress, who shot him in a fit of anger. J.R. did not press charges, as Kristin claimed she was pregnant with his child as a result of their affair.
Production for the 1980–81 season began in June 1980, but Hagman—who had begun the show in a secondary role but now was the star—refused to film the show without a raise. He returned to work ten days later with a new contract that paid him $100,000 per episode and royalties from J.R. Ewing merchandise. Viewers had to wait an additional two months to find out the answer to the famous question, however, as a strike by the Writers Guild of America began in July that delayed the production of most new network shows by eight weeks. During the delay, CBS showed early Dallas episodes featuring J.R. Ewing, helping the show's many new fans better understand his character.