This movie is one of the most authentic bio-pics ever made. There is a book called- 'Jail Diary and Other letters' (by Bhagat Singh), which are real letters and journal entries written by Bhagat Singh in his last 2 years in Jail. The dialogues, character ideology, philosophy, events of the movie stay authentic and true to the reality as much as possible.
These freedom fighters including Netaji Subhash Chandra Bose (movie 'Gumnaami') have not received enough recognition or respect in contemporary India for their work, patriotism and sacrifice - owing to our present and previous governments only highlighting the achievements of several few.
This movie is an absolute Gem with brilliant acting, direction, editing, screenplay, dialogues and Music. It transports you to the era of these unbelievable souls.