E109. Murderer Politician

Roshni is Rajeev Desai's Sister, who is a politician. Roshni informs her brother, Rajeev Desai that she wants to get married to Neeraj's Son, Rajdeep Mehra who is in the opposition party and he fumes in anger. Later, Rajdeep is found dead and Rajeev gets arrested. Who killed Rajdeep Mehra?