Set in 1960 in Bihar and based on a true story, the film is about a man who carved a path through a mountain in memory of his wife.
"In the film, we had to go very close to reality and for it, I needed a character who is very connected to his roots and can do justice to the role," said Mehta in an interview Wednesday.
Ketan is awed by Nawaz's performance in his film.
"Nawaz is an excellent actor. He has put in his hundred percent to play the character. He has put in his heart and soul into the film. His immense hard work is visible in his great performance," said Mehta.
The film also stars Tigmanshu Dhulia, Radhika Apte and Prashant Narayanan in key roles.