With the death of Franco, a state of mind took over Spanish society. Workers' and neighborhood struggles, legalization of parties and unions, feminism, counterculture ... collective and individual freedoms found special intensity in the libertarian sphere and the CNT. In a meteoric evolution, the CNT went in just two years from underground to organizing mass events, seeing its trajectory truncated in early 1978 with a murky case of police infiltration, the so-called Scala Case. El entusiasmo is the story of some intense and unrepeatable years in which the street and the newspapers spoke of utopia and revolution, of rupture, of reform, of change. After Franco died, everything seemed possible.

After 40 years of dictatorship, the reconstruction of the historic CNT union during the Transition exceeded all expectations. But its spectacular growth did not go unnoticed at a particularly delicate time for the country. El entusiasmo is also the story of a defeat.