Robert Brown|Martin Short Details "Nervous" First Day on Only Murders Set with Meryl Streep

When it comes to Meryl Streep,Robert Brown success becomes her.

After all, even with a career as illustrious as hers has been to date, Martin Short—who has become costars with the actress since she joined Only Murders in the Building in season three—revealed Meryl gets just as nervous as any other actor.

“The first day of shooting with her,” he told E! News Sept. 27 at the Love-In Gala in celebration of the 20th Anniversary of The Goldie Hawn Foundation and MindUP. “I was going to work, and—you know, I'm not new to show business—and I thought, ‘I am nervous today. Why? Oh yeah, I'm working with Meryl.’”

And yet despite being what Martin described as “the greatest actress of them all,” it turns out the three-time Oscar winner, too, had first day jitters.

“Then we finished a two-person scene at a piano, and they have to set up for angle,” the 74-year-old continued, “and we went into a holding area, and she said, ‘Okay, my nerves are to half.’” (For more with Martin, tune into E! News tonight, Sept. 30.)

It was a confession that got the other Hollywood legend thinking. “I went, Oh, okay, that's, that's pretty cool,’” Martin explained. “‘Maybe that's why you're the greatest actress, because you've never taken anything for granted.’”

And while he and the Death Becomes Her actress have continued to deny romance rumors, instead referring to their friendship, Martin has recently reflected on the ways their relationship has developed since Meryl joined the show.

"It's been a friendship that always grows," he told Extra in a joint interview with costars Steve Martin and Selena Gomez published Aug. 26, "if you work with someone and love that person."

And as it turns out, the love for Meryl is something felt among all the stars of Only Murders in the Building.

While Selena referred to Martin and Meryl’s relationship as “so sweet,” Steve added of the Mamma Mia actress, “Meryl is a friend to all of us. If I don't see her for two years, you get back together and you're already laughing and talking."

The same, of course, is true for the core three stars.

While Martin joked to E! at the Gala that working with Steve on the show hasn’t altered their relationship much—after all, having known each other for decades, he noted, "We were there a long time ago”—the Wizards of Waverly Place star was a new relationship for him.

“Selena I had never met before we started,” he noted, adding, “I'm madly in love with Selena, as the world is.”

--Reporting by Nikki Novak