Timothée Chalamet drops by “The Ellen DeGeneres Show” on Friday to talk about his role in the critically acclaimed film, “Beautiful Boy,” and explains what exactly that sequin harness he wore to the Golden Globes as all about.

The rising star tells DeGeneres that attending awards shows is still a “surreal” and “never-wracking” experience, but that hasn’t stopped him from dressing for the part. Chalamet set social media alight on Sunday when he arrived on the red carpet in some sort of sparkly harness.

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“I thought it was a bib,” he explains. “They told me it was a bib.” The attire was actually the creation of Louis Vuitton designer Virgil Abloh, and it was indeed a bib, or as a Louis Vuitton press release called it, “an embellished bib”.

Photo: Michael Rozman/Warner Bros.
Photo: Michael Rozman/Warner Bros.

“I had a friend send me a thing,” Chalamet adds. “Like sex dungeon culture is a thing where you wear harnesses, so uh… I didn’t do it for that reason.”

The 23-year-old movie star brought his mom with him to the Golden Globes, which he tells DeGeneres is him making up for all the pranks he used to play on her as a kid. He then reveals that one of his most regrettable pranks happened while on a cruise ship.

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“We were pulling into port once and [my mom] was getting out of the shower,” he says. “She was drying herself off and she went on the balcony just to kind of go like ‘Woo!'” Seeing his opportunity for some childish hijinx, Chalamet jumped into action.

“To be funny, I locked the balcony door and pretended to be leaving the room. And I thought it’d really be funny if I actually left the room and like gave it a minute or two minutes or something, and then let her back in.” It was only then that he realized he didn’t have his room key.

“Was she naked?!” DeGeneres exclaims. “She was naked, yeah,” he confirms, beginning to regret his decision to share. “That’s not like a weird thing when you’re prepubescent, right? Maybe I shouldn’t have brought that up.”

The Golden Globe-nominated actor also chats about working on “Beautiful Boy”, where he plays a drug-addicted teen who has a strained relationship with his father, played by Steve Carell. Chalamet admits that he managed to keep his love for “The Office” hidden from Carell while filming the movie.

DeGeneres also surprises the “Call Me By Your Name” star with a clip from his first-ever acting job on “Law & Order”.