'Big Bang Theory's' Johnny Galecki on Suiting Up 'Star Wars'-Style at Comic-Con

The actor talks with THR about suiting up and surprising fans during the panel.
A masked Johnny Galecki

CBS' The Big Bang Theory has a way of really entertaining fans at Comic-Con.

During previous years, the show's panels have featured performances from the Barenaked Ladies performing Big Bang's theme song, producer Warner Bros. Television giving away a trip to space and this year, star Johnny Galecki making a surprise appearance -- in full Star Wars: Return of the Jedi costume.

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The plan had been months in the making for the panel, which was poised to put the spotlight on the show's writing staff. Instead, co-star Melissa Rauch (Bernadette) wound up as the hour's moderator and was joined halfway through by Galecki, who got the biggest laugh of the hour when he approached the microphone to ask a question -- in costume as a fan in costume.

"We decided to do something like that at the Critics' Choice Awards, and that's when the show publicist and I were talking about who was able to go and who wasn't," Galecki says. "I said, 'I am and I would really like to, and how do we do it?' At first I said, 'Why don’t you just have Melissa and I as the house band for the writers panel?'"

That's right, Galecki wanted to play his ukulele alongside Rauch's tambourine and entertain the Con crowd. Rather than steal the thunder from the show's writing staff, Galecki had a more obvious idea.

"As a cast, we are big fans of the writers. So why don't we stand up and ask a question and do it that way?” he recalled. "It's Comic-Con; all we needed to do was wear a Yoda mask or something."

Galecki said he came up with the idea of Princess Leia's Bounty Hunter and WBTV went on a search to find the right costume, eventually connecting with a woman who created one and actually wore it during her wedding.

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"I like all things that aren't gender-specific and I was thinking about a disguise to infiltrate the palace and I thought of the Return of the Jedi -- and it's also a badass costume," he says with a laugh.

Adds Rauch of the reveal: "That moment when Johnny was revealed, I have to say -- when he took off his mask, my heart started racing so bad because he was kind of like backlit, but there was no smoke, but it felt like there was just smoke around him," Rauch tells The Hollywood Reporter. "It was very electric in that audience at that moment."

Check out a video of Galecki's reveal, below.

E-mail: Lesley.Goldberg@thr.com