"We're hanging out and then it feels like it was an earthquake in the restaurant," Chalamet recalled. "It was epic."
While appearing on "The Tonight Show with Jimmy Fallon" Monday night, the young star recalled attending a birthday dinner for rapper Kid Cudi last January. But Chalamet, 23, was in for a surprise when Kimye and "SNL" star Pete Davidson also showed up.
Chalamet said it was an "epic" evening.
"Kid Cudi, that's my favorite artist ever. I wouldn't be acting without him, I wouldn't have pursued this crazy career without him," Chalamet began. "I just texted him on the morning of his birthday and he said to come to dinner. I did not know that's what I was walking into -- which was awesome but was surreal."
The "Beautiful Boy" star added that just being there with Cudi was "very surreal," and he had to go to the bathroom and send his friends some text messages. When Chalamet arrived at the restaurant, Davidson was already there.
"So it's you, Pete and then Kid Cudi," Fallon said. "And then how did you know Kim and Kanye were coming?"
"Well I got there and I had a sneaking suspicion, but there was not enough seats for everyone," Chalamet recalled. "And then we're hanging out and then it feels like it was an earthquake in the restaurant."
"It was epic," he continued. "You feel [the energy shift] and I turned around and I was like, 'Holy shit.' Like I feel like I'm in this now a little bit, but then I'm like, 'I feel like I'm too much of a fraud or something' so I'm like, 'What?! This is nuts.'"
Chalamet said he texted a couple of friends to get some reassurance.
"I went to the bathroom. Seriously I sent a text to friends like, 'Am I worth...like does this make sense?'" he told Fallon. "And they were like, 'Man, 16-year-old you would slap the shit out of you. You go back to the table.'"
"And then I went to the table and then it was fun, it was a good time," he added.
Chalamet was at the late-night show to promote "Little Women," Greta Gerwig's take on the classic Louisa May Alcott novel. Chalamet stars alongside an all-star cast including Saoirse Ronan, Emma Watson, Florence Pugh, Laura Dern and Meryl Streep.
The film, which hits theaters this Christmas, has already generated Oscar buzz. On Monday, "Little Women" received two Golden Globe nominations, including a Best Actress nom for Ronan.
See Chalamet talk more about the movie, below. "Little Women" hits theaters December 25.
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