Jerry Seinfeld always had the best on-screen chemistry with close friend Julia Louis-Dreyfus.
ET correspondent Brooke Anderson spoke with Seinfeld at the Kennedy Center in Washington, D.C., on Sunday, where he came to honor Louis-Dreyfus, who received the Mark Twain Prize for American Humor. The two starred in the beloved '90s sitcom Seinfeld together, and the 64-year-old comedian revealed his favorite on-set moment with Louis-Dreyfus.
"I think it was the Festivus scene," Seinfeld tells ET, referring to the made-up holiday meant to be an alternative to the Christmas season popularized by the show. "Yeah, that big table and we were all exhausted and it was Yom Kippur and I was fasting and we were just, we were a wreck, you know, and we're trying to do this scene, we were just laughing. Her makeup was running."
"I just remember we could be a total mess -- we were a total mess a lot of the times," he continues. "The parking garage, a total mess up until, like, five in the morning shooting."
Seinfeld credits the success of the show to Louis-Dreyfus, and said he knew just 30 seconds into her audition that she was perfect for the role of Elaine Benes, his ex-girlfriend turned good friend in the series.
"I always felt like she was the diamond, she was the sparkle of the show that really made it the right chemistry -- the right formula," he notes. "You know, I really don't think the show would have been successful without her."
ET spoke to 57-year-old Louis-Dreyfus as well on Sunday about her big honor, and she said the highlight of her career has been working with talented co-stars on both Seinfeld and her critically acclaimed HBO hit, Veep.
"Oh God, I mean I've had so many, but I would say first and foremost the biggest highlight of my career has being able to work in a number of very significant ensembles," she says.
She also playfully reacted to viewing a clip of her first ET interview, which took place in 1982.
"Fix your hair," she says when asked about any advice she'd give her younger self. "I'm not kidding."