psychiatric doctor is driven insane plagued by nightmarish visions of Zé do Caixão's (Coffin Joe) subterranean world of bizarre horror. Under analysis it is discovered that he has a pathological fear that Zé has sexual designs on his beautiful wife and this is causing his horrific and diabolical dreams. Unable to cure him, his fellow doctors enlist the services of José Mojica Marins, the creator of Coffin Joe, in an attempt to convince the patient that Zé does not exist but all is not how it might first appear.

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