We are in Spain, in the midst of the Franco-dictatorship. On the international stage, the Cold War is at its heights, and the Vietnam War is living its worst moments. The US-Americans have installed military base camps in Spain: lots of them in Andalusia, very close to a town that very few other places can equal in traditionalism and conventionality: Seville. The young Americans who have to go to Vietnam, and those who are on their way back, stop over in these military camps, and get in contact with an incipient cultural and revolutionary movement that is just beginning in Seville. They are the ones who pass on the spirit of counter culture to the Spaniards. This is the birth hour of the Spanish underground movement. A magic and astonishing movement that, between 1967 and 1972, made of Seville a reference point for cultural avant-garde with multiple contacts to California, London, Berlin and the Northern European countries (like Sweden and Denmark). A movement that meant the first mayor change in Spain, that contained the germ of the change of mentality and behaviour in this country. And, in the most unfavourable conditions one can imagine, the first opening-up towards abroad. During five magical years, full of creativeness, some incredible characters completed some crucial, supreme experiences in order to overcome the dictatorship’s and the war’s monotony and gloominess, and to try to live an authentic liberty. Characters like Julio Matito, son of an army officer, who at the age of 15 became part of the legion, at 17 entered a Franciscan monastery and at the age of 18, expelled from the monastery, built up one of Spain’s legendary Rock bands: Smash. Or like Nazario, creator of the Spanish underground comic strip and intermediary between the Seville and Barcelona sections of the movement. We will get to know the contact points with California, London and Stockholm and the reason why Jim Morrison, on the way to Morocco, stayed in Seville for a certain time, amazed at what he was seeing… We will get to know how the stewardesses of the airline Iberia, on their way back from London, carried Acid packets in the buttons of their uniforms and why thousands of young Europeans and Americans came to enjoy this avant-garde, while the facts were totally ignored by the regime of General Franco. But, most of all, we will recover a time that was fantastic and liberal, the fundamental years of a powerful international movement: Underground. For one of the ironies of fate – the cultural encounter via US-American military base camps-, it came to materialize in a town that, up to that moment, had been inexistent for the rest of the world.