 The film received widespread critical acclaim . It pioneered the new wave cinema movement in Malayalam cinema and became one of the first Malayalam films to use synchronised sound and outdoor locales . The film also became the first Indian film to use sound as a leitmotif . It was shown at various film festivals around the world , and won four National Film Awards at the 20th National Film Awards in 1973 , including Best Feature Film , Best Director for Gopalakrishnan , and Best Actress for Sharada . 
