The narrative shifts into a complex emotional "index" of their lives:
The music, composed by with lyrics by Sahir Ludhianvi , was a massive success. "Mere Dil Mein Aaj Kya Hai" – Kishore Kumar index of daag 1973
The film tells the story of a young couple, Sunil and Sonia, whose newlywed bliss is shattered. While on their honeymoon, Sonia is attacked by a wealthy man, Dhiraj (Prem Chopra). In a desperate act to defend his wife's honor, Sunil kills Dhiraj. The narrative shifts into a complex emotional "index"
Loosely based on the 1886 novel The Mayor of Casterbridge by Thomas Hardy. Soundtrack Index Sunil and Sonia
– Sung by Kishore Kumar and Lata Mangeshkar