In a near-future New York reshaped by successive pandemics, mandatory digital identities, and pervasive drone surveillance, nurse Margarita Barraza discovers an elegantly dressed woman collapsed outside her hospital in the rain. With no identification and no digital signature, the woman defies all classification. Detective Paul O’Neill is assigned to investigate. What begins as a routine inquiry spirals into an encounter with a clandestine network of welfare workers, geneticists, and the urban dispossessed who exist entirely outside state systems. As the investigation deepens, relationships form and fracture, loyalties are tested, and the weight of grief becomes inescapable. Dementia explores, with quiet urgency, the human cost of a society that has learned to erase those it can no longer use.