Luke Bryan, Lady AntebellumA screenwriter for a big-league movie studio couldn't have dreamed up a better plot. Take three friends, have them write a song; have one of the friends record the song and release it; take the other two, who are part of a group, and have that group release a different song at the same time. Then sit back and watch the two songs climb the charts, both reaching the Top 5 at the same time, competing for that coveted No. 1 spot. In this movie, the group's song hits No. 1 first, then stays there for four weeks, effectively keeping the friend's song from reaching the top.

That doesn't sound like a movie to Luke Bryan and Lady Antebellum, because, like a real-life country song, it's what happened to them. Dave Haywood and Charles Kelley of Lady A co-wrote 'Do I' with Luke. And when the third member of Lady A, Hillary Scott, heard the song, she was insistent that Luke record it. The singer was finally convinced, and cut it for his sophomore album, 'Doin' My Thing,' and it was subsequently released as a single.

At the same time 'Do I' was released, Lady A was coming off their first No. 1 single, 'I Run To You' and released 'Need You Now,' which began to climb the charts. The friends watched each week in disbelief as their songs ascended side by side, with Lady A's tune reaching the pinnacle first.

"We were calling the label and telling them to stop working our record and let Luke's go No. 1," Charles tells The Boot. "They just said, 'No we can't do that.' As songwriters, we really wanted that song to go No. 1. For us as a group, having 'Need You Now' go number one for one week was great; it meant we had reached our goal. We just wanted the same thing for Luke."

Luck held out for Luke, and 'Do I' eventually did hit the top spot on the country charts. The writing partners were celebrating that chart-topper Tuesday night at a party sponsored by performing rights organization BMI, which claims all three songwriters as members. Held at the trendy Icon condominium complex near Nashville's Music Row, Luke's parents and in-laws were in attendance, as were his wife, Caroline, and 22-month old son, Bo. Young Bo even tried to get in on the action by climbing onstage with his dad, grabbing one of the silver mugs that were to be handed out by BMI. Absent from the festivities was the third member of Lady Antebellum, Hillary, who was sick and unable to attend.This forced Luke, Dave and Charles to perform 'Do I' as a trio, jokingly calling themselves Boys in Black because they were all wearing black jackets. The crowd of industry VIPs enthusiastically applauded their effort and the success of the No. 1 tune.

'Do I' isn't Luke's first No. 1 as a writer. He penned Billy Currington's 'Good Directions,' but says it's very different to have a No. 1 that he both wrote and performed. "To be the artist and the guy who sang it and got to the top of the charts is a pretty amazing experience," says Luke. "When I moved to Nashville, I knew I wanted to be an artist, but I dove into songwriting and did a lot of that. I still sometimes have to realize that I am an artist. The fact that I've had a No. 1 song [I wrote] as an artist is still surreal. It's gonna take this day to make it all really feel real."

The realities of the business will bring Luke, Charles, Dave and Hillary back down to earth immediately. Both have new singles; Lady Antebellum's 'American Honey' has already climbed to the Top 20 while Luke's 'Rain Is a Good Thing' is just behind them in the Top 40. Luke continues his trek on Jason Aldean's Wide Open tour on Feb. 19 in Highland Heights, Ky., while Lady A gets ready for the opening date on Tim McGraw's Southern Voice tour Thursday, Feb. 11 in Omaha, Neb.