Amitabh Bachchan is shy while singing: Amit Trivedi

"Bachchan saab called me directly. He wanted to meet me. So I visited him where he narrated me the story and gave me a brief of the show."So I'll say the song is jointly created by us. He has collaborated with me. It's Bachchan saab's idea, his plan and my execution," he added.Trivedi is elated with the song and hails it as a "once in a lifetime opportunity" to work with the "Deewar" protagonist.