Based on criminal court cases found in archives and newspapers, this article traces how the diagnosis of hysteria functioned in trials and Dutch forensic psychiatric practice ca. 1885–1960. Informed by Science and Technology Studies and praxiography, hysteria is studied as a ‘fire object'. It can make multiple relations with gender, which can be absent or present. This approach asks whether and how gender is important regarding hysteria. Gender only ‘stuck’ to hysteria in certain situations. In rape cases, hysteria took the form of lying and was connected to women. Although a woman's hysteria could be used as a reason to exonerate the male perpetrator's crime of murder, a man's hysteria never served to exculpate a female perpetrator of a crime. Signs on the body appeared to be very significant but did not suffice for a clear diagnosis. Inconsistencies during the psychiatric examination of the body therefore needed to be coordinated by pointing to other bodily symptoms, personal life stories, academic literature or logical reasoning. To analyse the ways hysteria functioned as a versatile fire object in the courtroom and pre-trial investigation alerts us to hysteria's shapeshifting potential that might explain the power of the hysteria label in twentieth-century medicine and culture.