"I was in London alone, doing Black Widow, on this app [Raya], going on dates and stuff," Harbour, 47, told British GQ Monday about first connecting with Allen, 37. "And yeah, I started texting with her, she was in Italy at the time — we got together, went on a date at The Wolseley, and it was, you know, she's f---ing unbelievable."
Harbour also recalled "the exact moment" that he fell in love with his wife, whom he married in September 2020.
"It was our third date. I was just in this phase where I was like, 'I'm just going to be brutally honest about everything,' because why lie? And I told her something about my life, about my beliefs," he shared.
"It would take a really extraordinary person to be accepting of the things that I said," he acknowledged. "And I remember thinking: Wow, that's somebody I want to be around."
David M. Benett/Dave Benett/Getty
Harbour said that Allen was faster to fall head over heels for him.
He joked, "She claims to have fallen in love at first sight with me — I mean, who wouldn't?"
Last week, Harbour also opened up about their first meeting during an interview on The Late Late Show with James Corden.
"She said when I saw you, I saw the biggest person I had ever seen in my life and also the smallest person I had ever seen in my life," he recalled of their first date. "Isn't that interesting? That's what made her fall in love with me — that I was very big and also very small in a certain way."
Harbour also teased about what fans can expect from Stranger Things' finale season.
"There's like, huge rift earthquakes going through all of Indiana, one would assume," he told British GQ. "So I don't know what the f--- is gonna happen in season 5 now."
He added, "I think as soon as the show ends, or maybe six months before it ends, you'll be hearing about whatever spin-offs they have planned."
Courtesy of Netflix
Harbour is also open to another actor taking on the role of Hopper.
"At this point, I think Hopper is a character that can exist independent of me," he explained. "If they wanna go back in time, forward in time … I'd love to see another actor play Hopper, and see what they can bring to it."
The actor suggested Euphoria's Jacob Elordi as a good candidate to play a young Hooper, saying, "He could pull off being as handsome as I was at 20."
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Seasons 1–4 of Stranger Things are available to stream on Netflix.