The singer chatted with ET about singing with Perry, calling it 'nuts.'
The video for the pop-country collaboration starts with Thomas Rhett rocking his signature double denim as he sits alone in a blue room and sings the opening verse. As Perry arrives on the track, she sits in a blush-toned room wearing a delicate white dress as she sings next to a guitar.
While the pair sing the song's bridge and have an intense walk through sheets, they meet -- and Perry has a wardrobe change -- as Thomas Rhett plays the guitar while they finish the rest of the video singing to each other.
Rhett celebrated the music video's release. "Working with Katy has been a really collaborative process," he said in a statement. "From tracking the song in the studio, to performing on it American Idol, to this video - her input has made this whole experience really special for me."
I loved being able to create a dreamy world for 'Where We Started,' going back to the Nashville singer-songwriter roots of where I started," Perry said in the same release.
In April, Thomas Rhett dished to ET about the collaboration and how it came to be.
“I had no part in that. My record label called her and said, ‘Would you want to do a collab with Thomas Rhett?’ and I thought they were crazy,” the 32-year-old singer told ET’s Rachel Smith backstage during the CMT Music Awards. “I was like, 'She has no idea who I am.' They sent it to her, and she loved the song.”
The "Slow Down Summer" singer also dished to ET about finally meeting Perry and how she took the tune to the next level.
"She loved the song and the next week she put her buckle on it and got it back and I was like, 'This is what it is was supposed to be," he said about Perry's verse. "And since then we shot a music video, finally got to meet her in person. She’s as sweet as could be and I just think she took this song from good to great."
The pair didn't just bond over the music. Thomas Rhett shared that both of them being parents of daughters added an extra touch to their new friendship.
"In between every take they had to tell us like, 'Hey, we're shooting,' because we'd be in the middle of talking about what our kids did and how we reacted to it," he said. "So a cool friendship, and hopefully I can catch her show in Vegas."