Carrie Underwood enjoyed her 23rd time at the top of the charts with her single "Heartbeat," from her 2015 album Storyteller. The song, written by Underwood along with Zach Crowell and Ashley Gorley, shows a softer, more emotional side of the married singer than some of her other hits, including two of Storyteller's other singles, "Church Bells" and "Dirty Laundry." Sam Hunt joins Underwood on the track, providing background vocals, and below, Underwood, Crowell and Gorley, share the story behind the romantic tune.

Carrie Underwood: Zach Crowell and Ashley Gorley came in to write with me that day. They had some stuff going, some ideas, and Zach’s so good at putting together music and grooves and things like that … Of course there’s always about 20 different ideas that everybody’s working on at all times, right? So it’s like, "Well, if you like it, we can go with it, and if not, we can find something else," and I said, "This is really cool. Let’s live here for a bit and see what happens."

It’s so simple. The word "heartbeat" isn't in a ton of songs, but it just seemed to be so honest and refreshing, the way we started writing it, things that we would want our lives to be, a simple kind of love. Everybody gets so busy and caught up in everything. You’re always -- at least I’m always -- trying to hang out with a million different people all the time. Sometimes you just want to be like, "Can it just be me and you for a second?" and I feel like that’s kind of where it was coming from, and everyone can relate to that.

Ashley Gorley: [It was] the first time us three had collaborated. Zach had a few tricks up his sleeve, just some different vibes and feels and different songs. That one, when we played through that one, it had a nice little R&B love flavor. I know Carrie can go ‘90s R&B with me … For that day, it sounded like that’s what it was supposed to be like, so we took off with it.

Zach Crowell: With "Heartbeat," a lot of what you hear on the record is from the demo. Pretty much, demos are demos of the thing, and you put some real drums on it and mix it a little more, and you get a super-great vocal. [In this case,] there’s a little more detail, but they’re pretty similar.

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