Katy Perry releases new song 'Dark Horse' featuring Juicy J

Katy Perry, whose single "Roar" is N°1 worldwide, took to Twitter to announce the release of "Dark Horse" on iTunes, tweeting to her more than 42 million followers, "Here she is!!! DARK HORSE ft. @therealjuicyj PREORDER PRISM. ENJOY (and thanks for waiting)."

The song, a mid-tempo hip-hop-infused track featuring Memphis, Tennessee rapper Juicy J, is a departure from Katy's "Roar" and previous pop releases. A preview of the song is available on iTunes, where fans can download it instantly when preordering her new album.

The song's lyrical content references a callout to a lover who doesn't know what is about to come his way, with Katy singing, "So you wanna play with magic / Boy you should know what you're falling for / Baby do you dare to do this / 'Cause I'm coming at you like a dark horse."

Katy called upon her fans to select the song as one of several "Prism" preview tracks, rather than as an official follow up single to "Roar."