Dark Horse

This Dr. Luke produced ballad finds Katy with her sights set on a guy, and she won't take no for an answer. It was selected as a promotional single from Prism after the singer asked fans to choose between this song or the dance club heavy "Walking On Air."

The song features a verse from Juicy J. The Memphis rapper told RapFix Live host Sway Calloway about their collaboration: "Dr. Luke gave me a call and was like, 'Hey man, Katy Perry wants you to feature on one of her songs for her album' and I was like, 'Wow.' I couldn't believe," he said. "He sent me the track over, I did the verse and like a week later he called me again and he was like, 'She wants to meet you she wants you to come to the studio.'" The recording process was something new for the rapper. "It was a little different. I did a lot of different versions to it. I recorded almost three verses because I wanted to make sure everything fit with the song and that she was satisfied," Juicy J said. "So it was a little challenging to make, but I've been doing this for a long time and I had fun doing it so it wasn't a problem." Dr. Luke also served as executive producer on Juicy J's Stay Trippy album.

The term "Dark Horse" is used to describe a person whose abilities or possible course of action are unknown, or to a somebody who reveals unsuspected talent. The earliest-known use of the phrase was in novelist and future Prime Minister Benjamin Disraeli's 1831 novel The Young Duke: A Moral Tale Through Gay. He described a horse race where, "a dark horse, which had never been thought of... rushed past the grandstand in sweeping triumph."