You may not recognize her face, but she's the face behind some of Hollywood's biggest hits. Katy Perry's good friend, singer-songwriter Bonnie McKee is responsible for penning her BFF's chart-toppers like "Teenage Dream," "Part of Me" and "California Gurls," and recently revealed to MTV News that she and Perry have been working on a new sound in the studio for Perry's upcoming fourth album.
"We were just in [Katy's hometown of] Santa Barbara and we wrote three or four songs, I guess. So I have four songs with her coming out," McKee told MTV News.
Perry recently appeared in McKee's viral music video for her own song, "American Girl" off her own upcoming album, which features a star-studded cast of her A-list friends singing along to the new track, from Katy Perry herself to Ke$ha, Macklemore, Adam Lambert, Jewel and even Kathy Griffin, along with a slew of others.
McKee emphasized that her BFF is evolving artistically. "I think it's a little bit more grown up, and it's really interesting," she said. "I'm really excited for the world to hear it because she's just - she's taking a new approach. And I don't want to say too much about it, but it's definitely different. It's definitely a little more mature than the 'California Gurls' of yesterday."
McKee has written for Britney Spear's "Me Against the Music," Taio Cruz's "Dynamite," Ke$ha's "C'Mon," among many others including artists from Kelly Clarkson to Christina Aguilera.
"Katy and I are really similar," McKee told MTV News. "That's kind of how we became friends. We met at Wasteland on Melrose [Avenue in Los Angeles], a thrift store. We just are totally on the same level...We're just soulmates in that way, I guess."
In addition to collaborations with McKee, Perry's fourth studio album will feature a track called "Double Rainbow." She has worked with Sia, Dr. Luke and Max Martin on her new music, and announced in April that the album is "halfway done." She added that the album will contain darker elements than her previous records, according to Billboard.
McKee's first album "Trouble" debuted in 2004. Her upcoming album will be her second in nine years.
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