Castillo was born in Calexico, California, and is founding member of The Latino Theater Company.
[2] He co-wrote the company's plays Stone Wedding and August 29.
[2] In 1997, Castillo created Four Brown Hats Entertainment (FBHE), a film and theater production company.
Following this, he wrote and directed Veteranos: A Legacy of Valor, a theater piece honoring the military contributions by Latinos in America's defense.
[5] Among his completed feature film scripts are Yo Solo, The Cobra, Valley of the Dead, Deerdancer, and The Last Angry Brown Hat.