Inside Taylor Swift's Sweet Connection to The Summer I Turned Pretty Series

It's been anything but a cruel summer for author Jenny Han.

Her new TV show The Summer I Turned Pretty, which is based on her young adult trilogy, premiered on June 17 and was the most-watched series on Amazon Prime Video by the end of the weekend. But for Han, the icing on the cake came weeks before the show even dropped when the first trailer debuted Taylor Swift's version of "This Love."

"I don't even know the words for what that meant to me," Han exclusively told E! News. "That was my no. 1 dream, to get one of her songs on this show."

Mission accomplished. Two of the finale's most pivotal moments are set to Swift's songs, including the return of "This Love (Taylor's Version)", which plays as Belly (Lola Tung) and Conrad (Christopher Brinley) have their first kiss on the beach. Swoon.

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And before that final scene, "The Way I Loved You (Taylor's Version)" serves as the needle-drop when Conrad finally steps in to dance with Belly at the debutante ball. Chills, reader, we had them and we weren't the only ones moved by the choice.

"That was my favorite moment," the show's lead told E! News. "It's really unbelievable. It was magical to film and everything came together perfectly."

It also brought everything full-circle for Han, who revealed that she "almost dedicated" the second book, It's Not Summer Without You, to Swift in 2010.

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"I was listening to Fearless and I was like, 'These songs have really helped me get to the finish line,'" Han explained. "When I write books, I like to listen to music to help me see the emotional vein of the story and her music really did that with me for the series."

But, as much as it meant to Han to have Swift's songs in the show, she knew it would deeply resonate with fans "because it's been so many years since the first book came out and so many people have been connecting her music to the story," Han explained.

"I knew what it would mean to me and I knew even more what it would mean to the people who have held these books really close to their hearts," she continued. "That just felt like the best gift I could ever give."

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The significance of two writers who are both revisiting their previous work with fresh perspectives coming together wasn't lost on Han either.

"I've always admired her as a songwriter and the way she tells stories through her music," she said. "It's fun that we got to do Taylor's Version and she's reimagining her music also, the way I'm reimagining The Summer I Turned Pretty. It's just looking at something that you made years ago and reapproaching it and what does that look like today?"

And now, the two women will always have Summer.

The Summer I Turned Pretty is streaming on Amazon Prime Video.

Don't miss a brand new episode of E! News' digital series, While You Were Streaming, on Wednesday, June 22, on Twitter @enews! We'll be recapping the latest episode of Disney+'s Obi-Wan Kenobi.