Since Mickey Mouse was first debuted in 1928, does this mean that Mickey Mouse will become public domain in 5 years if the copyright law doesn't change?
Film that he's appeared in, however, is under copyright and yes, his earliest films could indeed fall into the public domain.
> When that expires, Steamboat Willie can be given away, sold, remixed, turned pornographic, or anything else. (Mickey himself doesn’t lose protection as such, but his graphical appearance, his dialog, and any specific behavior in Steamboat Willie—his character traits—become likewise freely available. This was decided in a case involving Sherlock Holmes in 2014.)
And at the end :
> And in 2024, we might all ring in the new year whistling Steamboat Willie’s song.
[1] https://standardebooks.org/ebooks/maurice-leblanc/the-extrao...
[2] https://standardebooks.org/ebooks/maurice-leblanc/arsene-lup...
There is also trademark law. You can show mickey mouse movies, but that doesn't mean you can create your own.
Trade marks are intended for consumer protection. As long as you made it abundantly clear (everywhere) that your work was NOT a Disney work, and that it was instead a distinctly branded other work which happened to include Mickey Mouse (even in a leading role), based off of the features of the public domain version of the character (and possibly mixing in elements obvious to contemporary authors in a generic sense), then it would PROBABLY be worth talking to an actual trademark/imaginary property lawyer to see if the idea is uniquely expressive enough to be a new work.