This work is a qualitative study with a methodological approach based on Social Representations, guided by the following question: how do nurses interact with psychiatric patients who show signs of aggression in an inpatient unit? The objectives were to identify the social representations that nurses have of psychiatric patients who show signs of aggression and to analyze how these representations influence the nurse/psychiatric patient interaction, favoring attitudes of distancing/approximation during the manifestation of aggression. The settings were two public psychiatric institutions located in the city of Rio de Janeiro. A total of 28 interviews were conducted with nurses. After analysis, the category "Alert, danger: a volcano about to explode!" emerged. It emerged that the manifestation of aggression, which is a demand, is understood by the subjects as a symptom of the disease, so it can be inferred that this representation will influence the nurse’s attitude towards the patient, favoring withdrawal during the manifestation of aggression. These professionals need to be sensitized.