She asked the camera "Okay, but what if Bridgerton was a musical?"
From there, she sings a song.
The first song is sung from the perspective of Daphne Bridgerton after she is left by love interest Simon Bassett.
Fellow singer an TikTok users Nick Daly dueted the song, which fans of the show and TikTok users adored.
A day after the video was posted, it had 1.5 million views.
"I can't even drink champagne without seeing your face," she sings. "Am I the one to blame? / When we're dancing in the same room / But you're an ocean away."
Since her first song was such a hit, Barlow has written a few original songs.
They include one sung from the perspective of both Bassett and Bridgerton while on their honeymoon called "Burn for You".
As the song is sung as a duet, Barlow provides lines which can be sung by a second person as Bassett.
The pair even got praise from the streaming giant.
She has also created songs for other characters such as Penelope Featherington, who sings about her crush ON Colin Bridgerton.
"Never as thin, never as perfect / Never for him, never deserving of the boy I love," Barlow's song goes.
"So I keep it all in / It's like I'm invisible in my own skin / Give up on the fictional fairy tale end / You're not Cinderella, you're just Penelope Featherington."
Series creator Chris Van Dusen praised the work of the singers.
Barlow hopes the fan-favourite Netflix show will be turned into a musical.
Bridgerton isn't the first original musical to be created on the platform. TikTok users also created a musical based on the cartoon film "Ratatouille".