Actual footage of Penitentes - a sect of Catholic religious fanatics who engage in self-flagellation - is combined with new footage about a murder. http://theendofbeing.com/2010/04/03/lash-of-the-penitente-exploitation-cinema-and-los-penitentes/: “According to Grindhouse Cinema Database, the film is generally considered lost and notes that, “heavy editing of the prints even resulted in a 35-minute version that has no scenes featuring [Marie] DeForest. This version, featuring Joseph Swickard, is known to be the version that’s mainly available on VHS today.”