Johnny Depp shot all of his scenes in eight days, but after filming was done he didn't want to leave. So he suggested to Robert Rodriguez that he play a small part, the priest that Antonio Banderas talks to in the church, and used his Marlon Brando impression.
The man Barillo hires as a body double was an assistant. There were no digital effects. The man looked as identical to Willem Dafoe as he did in the movie.
There is a kid dressed in a yellow T-shirt in all the films in the El Mariachi, suonatore di chitarra (1992) trilogy.
It was Johnny Depp's idea for Sands to wear tacky T-shirts. He even sent his sister to Florida to find the tackiest ones from tourist stalls.