In a Glass Cage (1986)
A former Nazi doctor-turned-pedophile, paralyzed from the neck down after a suicide attempt, is forced to accept a boy as his nurse under threat of blackmail: the boy secretly witnessed the doctor's torture and murder of another boy, and possesses the man's diary, which details his wartime experiments and his subsequent descent into pedophilia and murder. Before long, the boy displays his ambition to follow in the older man's footsteps. - IMDb
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