Carrie Underwood just finished a run at Number One on the country singles chart with the title track to her album Blown Away. But apparently, she’s not one to sit on her laurels.

She’s already got another single ready to roll out to radio.

Which song is it? According to a note she just tweeted to her fans today, it’s the song “Two Black Cadillacs.”

The next single is…”Two Black Cadillacs!” It’s certainly a favorite of mine! We’re going to shoot the video soon! It’s going to be great!

— Carrie Underwood (@carrieunderwood) October 31, 2012

The song “Two Black Cadillacs” was cowritten by Carrie with Josh Kear and Hillary Lindsey. As Carrie explained in a promotional video earlier this year, it’s an “epic dark story” about “two women who are both being done wrong by the same man.” One’s the wife, the other’s the mistress, but as Carrie says, “you root for them both, because it’s not their fault.”

And when they find out, what do they do about it? “Well,” Carrie says with a grin that’s somewhere between innocent and a little wicked, “they kill him.” Ouch! “It’s dark, it’s stormy, it’s dramatic, like a soap opera.”

The melody is murky and moody, with a tension that rises throughout the song and matches the storyline.

As Carrie noted in an earlier tweet, she wanted to unveil the news to fans herself, before she was asked the question during an interview.

Carrie’s tweet also noted that she’ll be shooting the video “soon.”

- Kurt Wolff, CBS Local