This article explores the relation between politics and biology in Catherine Malabou's work, traces the origin of her recent anarchist turn, and seeks to explain how the latter influences the concept of plasticity. Whereas the relation between plasticity, neuroscience and epigenetics reflected a certain affinity with Marxism in her earlier work, Malabou's recent claim that biology and ontology are anarchist remains opaque as to its grounding in her own thought and scientific developments alike. The article argues that the origin of (...) the metamorphosis of plasticity from a Marxist to an anarchist notion gives rise to a new metaphysics of biology that is based on the assumption that society needs to be brain-like, reflecting the networked structure of synaptic plasticity. The article also proposes a new reading of Malabou's three plasticities (negative, positive and the plasticity of the concept) in temporal terms. (shrink)