一个全身赤裸的年轻男人蹲在室内靠窗的一株树干上,目光呆滞。他就是芬尼克斯(Axel Jodorowsky 饰),被关在精神病院的一位患者。从小体弱多病性格孤僻的芬尼克斯,童年是在马戏班里度过的。父亲奥高(盖伊·斯托克韦尔 Guy St ockwell 饰)是马戏班班主,母亲嘉西娅(布兰卡·格拉 Blanca Guerra 饰)是空中飞人的演员。嘉西娅信奉拜物教,她供的神是个被两个兄弟奸杀的断臂少女。在她流血的地方,人们挖池贮水建起教堂,取名“圣血”。当神父发现所谓的圣血不过是红油漆水时,同意当地政府拆毁教堂。嘉西娅带领教徒反抗。当嘉西娅发现奥高与人通奸时发起报复,奥高拿飞刀斩去嘉西娅双臂,割脉自杀。芬尼克斯进入精神病院。在嘉西娅的唆使下,芬尼克斯逃出精神病院,成为了嘉西娅的“魔手”。A young man is confined in a mental hospital. Through a flashback we see that he was traumatized as a child, when he and his family were circus performers: he saw his father cut off the arms of his mother, a religious fanatic and leader of the heretical church of Santa Sangre ("Holy Blood"), and then commit suicide. Back in the present, he escapes and rejoins his surviving and armless mother. Against his will, he "becomes her arms" and the two undertake a grisly campaign of murder and revenge.