Actor Aamir Khan launched the first song of his upcoming film Secret Superstar. 16-year-old Meghna Mishra has lent her voice to Zaira Wasim who plays the lead role in the film. Meghna sang the song Main Kaun Hoon live for the media present at the event. Amit Trivedi has composed the music for the film. Secret Superstar is slated to release during Diwali.