Jan. 9, 2013 at 10:09 AM ET
The star of HBO's "Enlightened" popped up in the outside crowd Wednesday, holding her very own handmade sign promoting her series, and Al Roker naturally ventured over to see how she was doing.
"I was just doing 'Morning Joe,' and I said, 'Oh, Willie's (Geist) not here. I wish I could say 'hi.' And I saw him through the window (on the Plaza) and thought I'd try to wave to you guys."
Dern isn't the first star to pull such a fun stunt -- Shaquille O'Neal, James Brown and George Clinton have also given the show unexpected surprises in the past.
Roker invited her back inside, and Dern joined him and Geist in the studio (sans sign) to chat about her show, which is about to start its second season.
"Everyone keeps saying, 'We don't know what (my character) is going to do next,'" explained Dern. "It's a wonderful, subversive tactic and thank you HBO for letting us do it, but she in fact does become a whistle blower this season in her American corporation.... It's a lot of fun."
"Enlightened" airs on Sundays at 9:30 p.m., as Dern's sign indicated.
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