Ver en Cuevana. The documentary First of May explores the more than a century-long evolution of the celebration and the meaning of this day. The structure is composed of memories, newspaper excerpts, testimonies found in archives, etc. - all these passages are brought to life by the actors' voices, taking on the roles of journalists, factory workers, policemen, workers and ordinary people who watch May Day, sometimes with interest and verve, sometimes with distance or irony.