EXCLUSIVE: Behind the Scenes of 'Supergirl' With Special Guest Star Lynda Carter

Supergirl went fangirl when The CW show got a visit from TV's original Wonder Woman.

Supergirl went full fangirl when the CW show got a visit from TV's original Wonder Woman, Lynda Carter, and ET's Leanne Aguilera went behind the scenes with the cast.

"I'm playing the first female president," Carter dished to ET.

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The actress made her debut as commander-in-chief Olivia Marsdin on Monday's episode, defending the United States from an alien attack.

Supergirl star Melissa Benoist was absolutely giddy to have Carter on set, and she revealed one special tidbit that the iconic actress shared with her.

"She taught me how to do the spin," Benoist said with a giggle. "I learned the Wonder Woman spin from Linda Carter!"

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While Carter was thrilled to be a part of the series, she pointed out that there are some differences between her 1975 Wonder Woman wardrobe versus the 2016 Supergirl getup.

"I think [the Supergirl costume] is fantastic," Carter gushed. "It's a little more covered up than mine was. It was the '70s. People were not wearing very much."

Supergirl airs Mondays at 8 p.m. ET/PT on The CW.