Veteran writer and lyricist Gulzar has revealed details about the 1973 film Namak Haraam, particularly focusing on a misunderstanding that arose between Amitabh Bachchan and himself. The film, directed by Hrishikesh Mukherjee, starred Rajesh Khanna and Amitabh Bachchan in leading roles and explored themes of friendship, betrayal, and social justice.

According to Gulzar, the script of Namak Haraam had to be altered because Hrishikesh Mukherjee had made a promise to Rajesh Khanna to give him the death scene. In Hindi cinema, it is often believed that the character who dies is perceived as the hero, and both Khanna and Bachchan were keen on portraying that heroic image. Gulzar revealed that Amitabh Bachchan was unaware of this agreement and only learned about the change on the day of the shooting. This revelation left Bachchan feeling betrayed and hurt, leading him to not speak to Gulzar for several days.

Namak Haraam was a significant film in the careers of both Rajesh Khanna and Amitabh Bachchan. It was released in 1973, shortly after Bachchan's breakthrough role in Zanjeer, which marked the beginning of his ascent to superstardom. Before Zanjeer, Rajesh Khanna dominated the Hindi film industry. Namak Haraam explored the friendship between Vikram (Amitabh Bachchan), the wealthy son of a factory owner, and Somu (Rajesh Khanna), a middle-class man. The plot revolves around Somu's efforts to expose corruption in Vikram's father's factory, which leads to a clash of ideologies and strains their friendship. The movie was a box office success, becoming the fifth highest-grossing film of 1973.

The change in the climax of Namak Haraam reportedly created tension between Rajesh Khanna and Amitabh Bachchan. Rajesh Khanna's associate, Prashant Roy, claimed that Khanna believed Bachchan was playing "dirty politics" during the film's production, suspecting that Bachchan had influenced Hrishikesh Mukherjee against him. This alleged suspicion and the altered death scene contributed to a strained relationship between the two stars, who never worked together again.

Despite the on-set tensions, Namak Haraam is remembered for its memorable music composed by R.D. Burman and lyrics by Anand Bakshi. The songs "Diye Jalte Hain," "Nadiya Se Dariya," and "Main Shayar Badnaam" became iconic and are still popular today.

The film also received accolades, with Rajesh Khanna winning the BFJA Award for Best Actor (Hindi) in 1974 and Amitabh Bachchan winning the Filmfare Award for Best Supporting Actor in the same year. Namak Haraam was remade in Tamil as Unakkaga Naan.