Within the scope of the R&D Project “History of the Visual Culture of Medicine in Portugal”, coordinated by the paper’s author, two large sets of photographs were retrieved at the oldest psychiatric hospital in the country, the Hospital Miguel Bombarda. The first set dates back to the late nineteenth and early twentieth century (before 1910) and the second and largest set dates roughly from the 1920s and 1930s. The authors are unknown and the medical reasons for taking them can be inferred from some of the clinical histories and the admission records. They aim at portraying schizophrenia, neurosyphilis, chronic alcoholism, sexual perversion, hysteria, microcephaly and other congenital deformities, meningitis, etc. They belong to the last days of golden age of the “grand renfermement” described by Michel Foucault, in the eve of the psychopharmacological revolution that brought about radical changes in therapeutics and care of mental patients, as well as a turn in societal attitudes towards them. They are reminders of a world that we are ready to regard as definitely not ours anymore, and to which we tend to look back judgmentally with dismay, sorrow and horror. More precisely, those photo shots document the shift in the history of psychiatry between therapeutic nihilism and the utopian social hygienism that sought effectiveness by resorting to the use of violent treatments of the mentally ill, from malariotherapy to insulin shock, from electroshock to psychosurgery, against the background of forced confinement and restraint. In Portugal, the use of medical photography can be traced back to the reception of both Charcot’s Iconographie Photographique de la Salpêtrière, of which first editions can be found in medical libraries, and the widespread use of the “bertillonage” techniques in forensic medicine. The use of photography in medicine, having enjoyed great favor as a tool to reveal the invisible (the optical unconscious) to the medical gaze, by capturing the reality of symptoms and stigmata finally frozen in truthful, objective proofs and thus replacing the rhetorics of narrative descriptions and speculations, has lost credibility and authoritativeness as medical styles of reasoning, concepts of health and disease and societal and political attitudes changed. However, the photographs in question can now be retrieved not only as icons of madness and deviance, but above all as illustration of the imagining of the homo demens by the medical gaze.