It was her favorite show, he said in a video interview with OnTheRedCarpet.com.
Henderson, a Dallas native, said he screamed at the top of my lungs in his car when he was asked to test for the part of John Ross Ewing III after his first audition. He called his mom when he finally got the part and said they both cried.
In the two-hour series premiere, Henderson's character wants to stake his own claim to the Ewing property of Southfork Ranch, especially after he discovered oil on it, but it looks as if his plans will be stymied by his uncle, Bobby Ewing, and just about everyone else.
Henderson thinks his late granny would still be thrilled even though she wasn't a fan of his character's bloodline.
But I know that she's looking down on me very, very excited, very proud and also probably really ready to get a little pissed off because I'm playing J.R.'s son, Henderson told the website. She loved to hate J.R., and she used to talk about J.R. to all my aunts and my uncles. And now that I'm playing his son, there's no telling what she thinks up there.
Dallas marks another high-profile television role for Henderson. He had a starring role on Over There, which looked at U.S. soldiers in Iraq. He had a recurring role as Edie Britt's bad boy nephew, Austin McCann, in Desperate Housewives and a short stint on the CW's 90210. His earlier television work includes the sitcom One on One.
His film roles include playing the jerk boyfriend to Jenna Dewan's character in the dance movie Step Up and the lead role in The Jerk Theory, which also co-starred Dewan. He will play a lovestruck teenager in the upcoming thriller Rushlights, which also stars Aidan Quinn and Beau Bridges.
Here's hoping nobody shoots J.R. III!