Appearing on the Late Late Show with James Corden on Wednesday, the Game of Thrones star told the hilarious story of the first time she met the Biebs himself, years after her mom gifted her with a life-sized cardboard cut-out of him in high school.
As her account goes, she was at someone’s house in Miami when she walked upstairs to get a tour — and ‘lo and behold, there he was.
“He’s sat there, shirtless, in this dark room, getting a head massage,” said Turner, 22.
“I was like, ‘Hi, nice to meet you, [I’m] Sophie,’ — played it cool, [then] ran into the closet and cried for like, five minutes,” she continued. “Then I came out with Joe and Justin goes, ‘Yo, Joe, I heard you’ve got a new girl?’ And Joe was like, ‘Yeah, there she is. She’s over there.’ “
So how did Turner respond? By bizarrely sticking her tongue out between two fingers, a move she recreated for viewers on Corden’s show.
“I don’t know what came over me,” she said, laughing. “Joe has never let me live it down since.”
And while her fiancé ushered her out of the room before she could see Bieber’s reaction, she’s pretty sure he was unfazed.
“I’m sure he’s used to it,” she said. “It can’t be the strangest thing anyone’s done to him!”
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Turner and Jonas, 29, got engaged last October after about a year of dating.
“[We] love the way that Joe loves her and the way that she loves him,” the singer’s dad Kevin Jonas Jr. previously told PEOPLE. “We’re a blessed family to have her as our future daughter-in-law — and, in our minds, [she’s] already a daughter-in-law!”
The Late Late Show with James Corden airs weeknights at 12:37 a.m. ET on CBS.