Katy Perry will return as the voice of Smurfette in movie "The Smurfs 2," but Britney Spears is apparently lending her voice to the movie as well.

Britney Spears will release a new song "Ooh La La," written and performed for the end credits to "The Smurfs 2." The track was penned by Dr. Luke, Amoo, Cirkut, Bonnie McKee, J Kash, Lola Blanc and Fansisca Hall (phew!) and produced by Dr. Luke, Ammo and Cirkut. Director Raja Gosnell calls it "the perfect Smurf-party song." Spears' kids are apparently going to be fans as well.

“I have always loved the Smurfs as a kid and now my boys are the biggest Smurfs fans EVER. I wanted to surprise them with a song in the movie. I know they'll think it's Smurftastic!” she said in a release.

No confirmation on when fans can expect to hear the pop star's new song, but Columbia Pictures/Sony Pictures Animation film arrives in theaters on July 31. The live-action/animation hybrid stars Neil Patrick Harris, Jayma Mays and Sofia Vergara, with Perry as Smurfette and Hank Azaria as Gargamel. Brendan Gleeson joins the cast as Victor.

Spears has been also busy prepping her 8th, as-yet-untitled studio album.