A Mexican community is slaughtered by Confederate troops; the lone survivor, a boy, is taken in by a preacher. Years later, the boy is now a soft-spoken, devout young man with perfect shooting skills (despite being a pacifist). On his journey to help his half-sister out of a complicated situation, he crosses paths with the men who killed his family, unbeknownst to him.

E.C.H.O., a secret organization with a strange name masterminds a bizarre plot to take over the world by dosing important `nerve centers' with super potent LSD. The only man who can stop them is Rex, a secret agent working for an undisclosed organization.