Using the documentary S21: The Khmer Rouge Death Machine by the Cambodian filmmaker Rithy Panh, as well as reflections developed by anthropologists and philosophers, this paper returns to the “scene of the crime” where thousands of people were interrogated, tortured and executed. The objective is to see how a machine (film) attempts to understand the mechanisms of another machine, one that transforms ordinary individuals into exsanguinated animals. From this perspective, film no longer limits itself to documenting the work of death, it wants to show death at work. By revealing unusual situations that show the coming of an event and thereby provoke the ineffable of death, film both reveals and hides meaning. The genocide experience leaves traces, but not always those we expect.