Aubrey Plaza Recalls Leaving Robert De Niro a 'Little Freaked Out' on ' Dirty Grandpa ' Set

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Aubrey Plaza even had acting legend Robert De Niro unnerved by her commitment to character.

The actress, 38, recalled "weirding out" the Academy Award winner, 79, when they played romantic opposites in the 2016 comedy Dirty Grandpa as she appeared on one of London Film Festival's ScreenTalk sessions, according to Variety.

"I didn't really have a relationship with him off camera because he's him," she said. "I didn't have time to get to know him, he shows up in a puff of smoke and there's no chatting at the water cooler.

"By the time he'd show up, I'm in character. My character had one goal –– to have sex with him. I was acting totally insane as the character because we were about to shoot. I don't think he understood that wasn't me. You'd think he would because he's an actor and an amazing one," Plaza added.

She noted that her performance as the sex-crazed college coed Lenore apparently had De Niro so convinced, that one of her agents "heard Bob's a little freaked out."

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Plaza said that by the time she was out of character and showed up to a lunch he hosted for the cast and crew, De Niro was fooled once again. "I showed up and he's like, 'Who are you sweetheart?' and after that he was normal," she recounted.

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"At first I think I came on really strong. I did some questionable things I wouldn't do anymore," Plaza admitted.

In Dirty Grandpa, De Niro played Lieutenant Colonel Richard "Dick" Kelly, who tricks his uptight lawyer grandson Jason (Zac Efron) into taking him on a road trip to Daytona Beach, Florida during spring break.

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Plaza previously joked about building chemistry with De Niro on the set of the film as she appeared on Jimmy Kimmel Live! in 2016.

"We're soulmates," she said. "Robert De Niro's character lies and says he's a professor and my character has this obsession with having sex with a professor so I kind of zero in on him... He's met his match with me. He's a dirty grandpa and I'm a dirty girl."

The Parks and Recreation alum revealed that it took "a solid nine, maybe ten" hours to film their sex scene, adding: "There was a lot of interesting stuff that went down, you know. We didn't totally plan out the scene, so we didn't really know what was going to go down."

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"I'd try to get in there and suck on his nipples, and he was like batting me away, and I didn't know if it was in character or not," she said. "And then they'd cut the camera and [the director] called me back and was like 'Bob does not like his nipple area paid attention to.'

Plaza added: "I was like, 'Great, now he thinks that I wanted to do that.' It was a lot of really fun moments."