The secret of Alberto Portera (David Plaza, 2025) is a selection of fragments of an unpublished filmmaker so far: Alberto Portera. Neurosurgeon by profession, but interested in the artistic gesture, to which he dedicated numerous articles and essays, he recorded with his camera the artists of the group El Paso in action, in his daily artistic activity (Millares, Saura, Hernández Mompó, Canogar...). But he also recorded filming of Carlos Saura, clinical essays, trips, performances... Alberto Portera presents himself to us as a missing link between the tradition of classic documentary and amateur art and essay cinema. These films have recently been restored and digitized by the Juan March Foundation.