Kabir follows a train journey from Mumbai to Kolkata, where Yasmeen, a Muslim lady meets Abir, an aspiring photographer as both are travelling together. They both start chatting and find out about each other, until Abir slowly begins to show his dark personality. He reveals that he is a part of the Indian Mujahedeen, and is on the lookout of Imtiaz, a former IM terrorist, who later turned into a police informer and betrayed their cause. Abir is on the hunt of Imtiaz and holds Yasmeen hostage, as he belives Yasmeen knows his hideout. Both their background stories are revealed and are filled with suspense with the ultimate goal of serial blasts in Kolkata & Mumbai.