Linda Perry is an American singer-songwriter, musician, and record producer. She was the lead singer of 4 Non Blondes, best known for the song What's Up?. She released the solo album In Flight and scored the music for Out of My Mind and Luckiest Girl Alive (Soundtrack from the Netflix Film). Her most popular songs include Knock Me Out, Fill Me Up, and A Thousand Lifetimes, a collaboration with Glen Campbell. Perry has appeared in the series Make or Break: The Linda Perry Project.