Taapsee Pannu's and Amitabh Bachchan's starrer Badla has upped the anticipation level and with the first song of the film, the interest to watch the thriller has gone up by a notch. Kyun Rabba is no romantic dance number but a mature and important song to the narrative. Supported by Armaan Mallik's vocals, the song has been composed by his brother Amaal Mallik.