The veteran actor, who passed away on Friday, spent months battling cancer, but he refused to let his illness affect his career and continued working while he was undergoing treatment.
TV producers are currently shooting the second season of the relaunched "Dallas," in which Hagman reprises his role as oil tycoon J.R. Ewing from the original TV soap, and he had filmed several episodes before he was taken ill.
It has now been confirmed the show's writing team will have to alter the planned storyline in the aftermath of the tragedy.
Viewers had seen Hagman's character vowing to launch a titanic battle for control of the family's business empire at the close of the debut season earlier this year.
A representative for Channel 5, the U.K. broadcaster of Dallas, tells WENN, "Dallas is midway in production on Season 2 and this sad news will be incorporated into the storyline... The team are dealing with the death before they consider the writing possibilities."
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