"I'm always hoping for J.Lo to show up, just 'cause I really enjoy some J.Lo," the 44-year-old actress said.
Witherspoon and Dern asked fans who they'd like to see on the show and people responded with names including Julia Roberts, Frances Conroy, Brad Pitt, Amy Adams, Jennifer Lawrence, Alyssa Milano, Gwyneth Paltrow and Sandra Bullock.
"It's gonna be a huge cast," Dern joked. "And it's going to be so exciting."
As for the possibility of a third season actually happening, Witherspoon shared, "We want to do it, we're just kind of waiting... We're trying guys! We're trying to come up with the right story."
"[Nicole] just texted that we have to do another one right away," Dern said. "... I really do fantasize that we'll do it again because... [I] miss those characters. We're so lucky. They're just the best characters."
Dern emphasized her eagerness to return to BLL while speaking to ET last year.
"How can I say no to Renata?" Dern told ET of her BLL character. "I mean, she requires [all the memes], and I love her so much, so I'm thrilled for her that she's a meme, because she would really appreciate it. I could never say no to Renata."
Likewise, Nicole Kidman said she would "love" to do a season three.
"I think we would love to do a season three because there [are] certainly ideas," Kidman told News Corp Australia. "But we would not do it without all of the same people involved... even the kids."
When it comes to the network, HBO Programming President Casey Bloys told ET that he'd be open to a return to Monterey Bay.
"Never say never," he said. "... If they all came to me and said, 'We have the greatest take, listen to this,' I would certainly be open to it. But who knows? It just doesn't feel like it. But I'm certainly open to it."
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