'Dallas' producers hope to do ''right'' by Larry Hagman.

The actor passed away from cancer last November and an episode of the drama airing tonight (11.03.13) in the US promises to be an emotional send-off for the late star and his villainous alter ego J.R. Ewing

The actor's close friends and co-stars Linda Gray and Patrick Duffy - who play J.R.'s long-suffering wife Sue Ellen and brother Bobby - found filming the tear-jerking episode, 'J.R.'s Masterpiece', especially hard, and did their best to honour him with real emotions.

Mike Robin, the show's executive producer, said: ''They wanted to do right by their friend in terms of honouring him and honouring his character and so they worked so hard and they went to the emotional depths that [viewers will see].

''I mean that was an interesting thing. So much of that was real. After certain scenes, like when Linda [filmed her part at the] funeral... she says to me, 'That was so hard.' But it was very real.

''After shooting Patrick's moment,] I said, 'I think we did well,' and he said, 'Yeah, I think he'd be happy.' Everybody that was involved in it, that was what we were trying to do, trying to feel that we did right by our friend Larry Hagman.''

The heart-wrenching episode, which will continue a murder mystery plot in the style of the hugely popular 'Who Shot J.R.?' storyline from the original series, is a fitting tribute to the star and the cast felt like they were at a second funeral for their friend because of the special eulogies penned to fit both J.R. and Larry.

Executive producer Cynthia Cidre told AccessHollywood.com: ''A lot of what was said [in the episode], I think fits both people. It fits the fictional character and Larry, and so the actors who also knew Larry are kind of doing a like a parallel funeral for both actor and character.''