Anna Kendrick had already appeared in two hit "Twilight" films before being cast alongside George Clooney in 2009's "Up In The Air", but she still was a ball of nerves during her first day on set.

The actress appeared on "Who's Talking to Chris Wallace" last week while promoting her directorial debut "Woman of the Hour" and credited Clooney for going out of his way to her feel at ease.

Kendrick, who was just 23 during production of the film, said that Clooney did his best to help her feel like he was just another actor on set with her.

"To other people he is kind of capital G, George, you know?" she said of the then 47-year-old. "And he works really hard to make you forget that and feel comfortable."

While the two were preparing to shoot their first scene together — which for Kendrick was also her first scene in the entire film — the Academy Award-winner shared his nerves with his young co-star.

"He said, 'God, do you get nervous? On the first day, I get so nervous. Do you get insecure? I get really insecure.' And I was like, 'Yes, I do, George, I do. I totally get nervous. I totally get insecure,'" Kendrick said. "He was doing this whole thing about, like, 'I worry. Like, did they even hire the right guy?'"

"It was such a gift for him to say that," she continued. "Because it felt like 'Oh, okay, I can bring my anxiety into the moment and someone is going to hold space for that and be cool with that."

Kendrick said that it wasn't until years later that she realized Clooney was most likely not being entirely truthful.

"Suddenly that memory popped into my brain and I thought, 'No, no he does not get insecure or worry that they've hired the wrong guy,'" she said. "Maybe that's something he dealt with earlier in his career."

Still, Kendrick said that to this day she appreciates the gesture.

"It really, really set me at ease," she said. "And was a complete fiction."

True or not, Clooney's gesture helped Kendrick give her best performance. Kendrick would eventually go on to be nominated for the Best Supporting Actress Oscar for her role.

It's natural to feel nervous or insecure when starting at a new role. And though you won't have a George Clooney to help calm you down, it is possible to keep potential feelings of imposter syndrome at bay.

Be mindful about what prompts insecurity and those intrusive ideas, Judy Ho, a neuropsychologist and professor at Pepperdine University, previously told CNBC Make It.

She suggests noticing your patterns and what situations trigger you — what evidence supports the idea that you're incapable and what evidence contradicts it? Write down those findings in two columns and compare them.

The exercise may help you realize that you bring a lot more to the table than you might think.

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