Here in the United States, most of our favorite legends about America have been debunked by citizen rabble-rousers with competing political agendas to promote. But in Mexico, the people still love their legends. Doing the right thing, even if it means death, is still considered an honorable choice. An understanding for this difference is developed slowly for the audience. When realization hits during the final scenes, it packs a real wallop.
Every twist is set up early.
But to guess what happens next is not as important as enjoying what happens next. Early in the film we see this elaborately shaped two-shot revolver, with one handcrafted bullet still in the chamber. It was meant to be the most beautiful pistol ever made. And for a time it probably was. That bullet will be important later on, too.