Taylor Swift and Zayn Malik surprised fans when they teamed up for "I Don't Wanna Live Forever," their sensually-charged collaboration track from Fifty Shades Darker that was unveiled on December 9.

But just how did this unlikely musical pairing happen, exactly? The likely mastermind behind the collaboration was Zayn's on-again, off-again girlfriend and Taylor's resident squad member Gigi Hadid, Hollywood Life reports.

"It was Gigi who originally suggested they work on a song together. This was back in September, when Taylor was spending time with Gigi and Zayn after her breakup with Tom [Hiddleston]," a source told HollywoodLife.com. "Gigi brought up the idea when the three of them went out to dinner in NYC."

The site's source shared that it was only after Taylor and Zayn's initial meeting that the country-turned-pop superstar had the bright idea to team up with him on the Fifty Shades Darker track she was, at the timing, writing with Jack Antonoff.

"When the opportunity came for Taylor to team up with someone on 'I Don’t Wanna Live Forever,' she immediately thought of Zayn," the insider claimed. "It’s a sexy song, the perfect song for them to collaborate on."

Meanwhile, Gigi couldn't have been prouder of her two pop star friends: When the song dropped online, she made sure to support it on Twitter!

How the Men in Taylor Swift's Life Reacted to the Songs About Them:

More From PopCrush