A young man named Juan is released from a mental asylum after a long confinement. He is on parole and placed under the guardianship of his aunt but is he cured or still a danger to society? One thing is clear. Juan has no intention of going back to the sanatorium or following the rules of his release. In fact, he has a plan which involves an elaborate revenge on his aunt, three female cousins and anyone else he holds responsible for his confinement. The question of whether Juan is truly insane or just pretending to be is the question that drives the narrative of La Campana del Infierno (English title: A Bell from Hell aka The Bells, 1973), a Spanish psychodrama which is often categorized as a horror film due to its gothic atmosphere, disturbing imagery and sinister plot twists.