In the province of Santa Cruz the idea that “there are no more Indians” has been generalized as a consequence of two presuppositions: first, the idea that the tehuelche people (considered as “Argentinean Indians”) have been extinguished, and second, that the mapuche people are illegitimate (recent migrants coming from northern provinces or from Chile). State and scientific dispositifs built on civilizatory, racist and nationalist prejudices converged in a discursive formation according to which the supposed extinction was the result of a process of degenerative miscegenation (mestizaje). Such dispositifs justified the dispossession of their territories, enterprises that were oriented to “rescue” the “last pure Indians”, and the appropriation of their cultural practices and bodies as a patrimony both of the fatherland and science. From a corpus conformed by travel chronicles, archival documents, scientific reports, ethnographic observations, oral memory, interviews and informal conversations that took place between 2007 and 2009, this work examines the processes of invisibilization and re-visibilization of indigenous people in Santa Cruz. It tracks the indigenous agency focusing in a paradigmatic case: the passage of Camusu Aike from a disciplined “tehuelche reserve” to an autonomous “community”. The process of fighting for their recognition as pre-existing people and as a valid interlocutor exhibits a convergence of indigenous activism, oil exploitation enterprises, juridical norms, state policies and a committed Anthropology.