How did NGOs rescuing refugees in the Mediterranean come to be imagined as participants in criminal cartels? At the height of the 2015 migration crisis, a Sicilian Antimafia judge used a new legal paradigm to map the actors and institutions crossing the sea borders of Europe: the "criminal association." Once introduced, this legal imaginary spread across the continent. Investigations alleging criminal associations between smugglers, fishermen and humanitarians, border forces, priests and anarchists, European Ministers and Libyan militias, have been the basis of political campaigns, the daily fare of mass media, and the fascination of national publics. My dissertation research is the first focused study of the rise of the political imaginary of "association" and its role in structuring the relationship between politics and migration in Europe. Through ethnographic and archival research in five countries, it tracks the discursive life of this juridical concept and its deployment as both an instrument of state repression and a weapon of resistance mobilized by migrants, humanitarians and, at times, states themselves. My preliminary research as a participant observer on board a humanitarian rescue ship offshore Libya and in a refugee transit camp in Lesvos (Greece) suggests that the imaginary of "criminal associations" emerged at the conjuncture of two major political and cultural shifts: on the one hand, the migration crisis, and on the other, the fiscal crisis of the Eurozone and the fragmentation of the continent's social and political unity. Bringing together methods from cultural studies, legal anthropology, and critical border studies, I examine how the forensic, legal, and political battles to map associations have transformed the Mediterranean migrant passage into a laboratory for negotiating the contemporary crisis of Europe itself, breaking apart old alliances and forging new political and social unities against the shifting landscape of a continent in crisis.