On a recent season of an Indian music show, a young singer from the northern state of Bihar performs a haunting, century-old folk song about separation, colonialism and longing. It tells the story of a woman watching her husband leave to fight in a distant war under British rule. She mourns his absence, curses the empire that claimed him and, at one point, imagines taking up a dagger herself. Performed by Bihar folk singer Utpal Udit in collaboration with acclaimed vocalist Rekha Bhardwaj,