Pop sensation Katy Perry tells her own incredible true story.

How does a girl from a sheltered Christian background go on to become a global superstar, selling 11 million albums worldwide? It's an amazing story, and now Katy Perry tells it in her own words. Katy says she was inspired by Madonna's 'Truth or Dare' documentary to capture a snapshot of her life with this blend of documentary and concert film. Archive footage reveals her strict religious upbringing, during which she was forbidden to listen to secular music. She also talks about her abortive early gospel singing career. But perseverance won through as Katy achieved her dream. Now she says her ambition with those colourful live shows is to make people smile, while her songs form a 'mad diary' of her life. There have also been bumps along the way, and Katy takes the opportunity to talk about her short-lived marriage to Russell Brand.