I somehow managed to finish The Three Musketeers (all 708 pages) and began on The Hunchback of Notre Dame. From what I've read so far, they're nothing like the movie versions you see, to say the least.
The Disney version of The Hunchback of Notre Dame, that everyone knows and loves, is very different from the book. Also, the Mickey Mouse version of The Three Musketeers doesn't show how fickle the protagonist, d'Artagnan, is. As I was reading it I kept a count of how many times d'Artagnan "fell in love" with a woman. Then after he "fell out of love" that female character would disappear for a time before coming back for some reason or another.
As it is known, the motto "all for one, one for all" came from The Three Musketeers but in the end, it doesn't stay that way. The four friends (yes four, three Musketeers and D'Artagnan, who doesn't become a Musketeer until the end of the book) fall apart at the end and go their separate ways. This can be reflected in society today as friends grow apart, whether it's because of a fight or because their interests change. It's interesting how easy it is to relate to literature almost two hundred years old.