When Sands buys gum from the kid on the bike, he tells him, "I never want to see you again." The next time the kid shows up in the movie, Sands has had his eyes taken out.

Danny Trejo, who played Cucuy in this film, is director's Robert Rodriguez's cousin. This might be why Trejo is in almost every film Rodriguez has made.

If you watch the credits right until the end, the camera starts zooming out to reveal that the credits have been coming out of Sands' eye sockets, he then replaces his glasses.

When El Mariachi is at the presidential party, he moves close to the President and asks him if there is any song who he wants to heard. The President says "La Malagueña". (Girl from Malaga). Antonio Banderas was born in Malaga, Spain.

The tag that the white dog of Mickey Rourke has says "moco." Moco was the man that killed Domino in "El Mariachi" (1992) and he always dressed in white.

The film finished shooting in 2001, but was pushed back until 2003.

Johnny Depp wasn't the original choice for Agent Sands. The original choice was George Clooney and had much more scripted swearing. Depp simply ad-libbed most of the parts where he was supposed to swear.

In the scene where El Mariachi is looking in his guitar case, you can see the throwing knives Cucuy was throwing at him in "Desperado" (1995). They are the ones with the big crosses secured to the lid of the guitar case.

When El Mariachi is in the hotel room with the guitar and has the flashback to when his wife is shot, the boxes on the bed say "Rodriguez," which is the director's (Robert Rodriguez) surname.

Director Robert Rodriguez knows this site all too well. In some of the features on the DVD like the "10 Minute Film School" and "Inside Troublemaker Studios", he tells us that he's gone back into the film and edited out shadows, equipment, crew reflections in any sort of glass, and other things. This is one of the rare times I've heard of a Director actually taking the time and effort to do this.