Amitabh Bachchan was offered to play the role of Mr India but he declined as he was into politics and was not doing many movies. Shekar Kapur wanted Anupam Kher to play the role of Mogambo but then switched to Amrish Puri as he wanted someone who looked scary.
This was the last film that the writing duo Salim-Javed wrote together. Although they had split much before in early 1980's, but they came back one last time to script this movie.
In 1957, Nanabhai Bhatt made a movie with the title of "Mr. X" in which Ashok Kumar played the role of Mr. X and invisible man. This was the first Hindi movie to be made with a invisible man as the theme. Interestingly, Ashok Kumar who played the title role in the 1957 movie plays a supporting role as Professor Sinha in Mr. India.
When Prof. Sinha is first talking to his students in the class, on the blackboard behind him are displayed formulae from varied branches of science - mathematics, chemistry etc. Prominently visible is "Boney's Law of Time-Space Continuum". Boney Kapoor is the producer of the movie.
The sequel which was announced its plot was that it would be after 23 years where is Mr India and what happened to the invisibility formula,and a new terrorist arrives who wants to rule India and it was announced that Salman Khan would play the terrorist.