Dr. Luis de Portillo' is an exchange teacher at Crystal Cove High School teaching honors courses in social studies. He knew about the legends of El Horrifico and taught them in his class. Mary Ann Geerdon learned about El Horrifico from him. For a while he thought he might be El Horrifico himself, until the gang proved that he was innocent.
Appearances
Scooby-Doo! Mystery Incorporated -- The Song Of Mystery