In a bedroom scene from the first episode, Jackson, who plays Reese Witherspoon's onscreen husband, Bill, is clad only in a white T-shirt and tighty-whities as he and Witherspoon's Elena bicker over their suburban lives. The moment garnered a slew of passionate reactions from fans online.
Little Fires Everywhere executive producer Liz Tigelaar zeroed in on Jackson's infamous underwear scene as an unexpected highlight from the eight-part series.
"I think it was his idea," Tigelaar reveals to ET. "He really wanted to do it because he felt -- which was true -- it was what dads wore then, which it absolutely was."
"What he couldn't see was how graphic it was," she adds with a laugh. "So, yeah. He says producers made him put on pajama pants after that, which I think he's blaming me for that. I don't know that I'm the one that suggested that, but I will say, I was very amused by the tighty-whities. It felt very accurate and it also felt very graphic. I was like, 'Whoa! I've seen a lot of Josh Jackson!'"
For Jackson's part, he took the fan response in stride, appearing on Live! With Kelly and Ryan last month to talk about filming that particularly revealing Little Fires Everywhere moment.
"I didn't realize quite what a hit those were going to be," Jackson admitted. "Who knew that all these years what was missing from my career was parading around in my tighty-whities?!"
The 41-year-old actor, who recently became a dad himself, welcoming a daughter with wife Jodie Turner-Smith, joked that as he's gotten older, he's grown to appreciate the thirst tweets.
"I'm in my 40s now. I enjoy being objectified," the Dawson's Creek alum said. "I watched it and I was like, 'Oh! Yeah, that's a lot.' Not a lot left to the imagination there."
Little Fires Everywhere is streaming now on Hulu.
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