The £1,000,000 note at the time the film is set, 1903, would be worth approximately $100,000,000 ($100 millon) in 2002. Or £65,000,000 Sterling. In 2020, adjusted for inflation, the 1903 £1,000,000 would then be around £122,391,759.22. The film would still work remade in 2020 if the note was still an impressive £1,000,000. Although, after the similar "Brewster's Millions" & "Trading Places" story versions, the figure would probably be revised upwards to £1,000,000,000 (a UK Billion).
The prop £1,000,000 note was larger in both size (about 7 x 9 inches) and value than any real note produced by the Bank of England up to that time, even notes for internal use. However, the bank still imposed strict regulations, which were violated when posters advertising the movie showed a reproduction of the note. This had to be covered over before the posters were allowed to be used.
Future film director Bryan Forbes can be seen as Todd, the tailor.
The plot for the 1983 Eddie Murphy /Dan Aykroyd comedy 'Trading Places' is loosely based on this film.
The details of the £1,000,000 note are shown in the background to the opening credits of the film: June 20th 1903 London.