Laura Evans accepted the role of Carmen before the script was complete.
The part of Gibson was the most difficult to cast since the director wanted someone who would not only be physically imposing but also have the fighting skills necessary for the end scene of the film. Jason McGuckian was almost not called in for the audition but Jennifer Ortega (the casting director) insisted on bringing him in. He ended up being cast and extended scenes were written for the character.
The club used for the opening action scene is the same "bar" used for the meeting between Gibson and Wes at the end of the film but with different lighting.
With the exception of the park scene all of the scenes between Carmen and Wes were shot in the first week of filming and in sequential order.
Melissa Dawn Smith's character of Sherri was added about a week before filming began. It was felt that the character of Nicolas needed someone to talk to.