The figure and biographical adventure of Joan Comorera embodies many of the greatness and misery of the first half of the 20th century: the brave and loyal political commitment, but also the obfuscated fanaticism of someone who conceives politics as a totalizing and dogmatic form of religion. Starting from Comorera, founder of the PSUC, a Catalan socialist and nationalist, a supporter of a Catalan communism not subaltern to the Spanish one and which would appeal to the proletariat and also to the incipient middle classes of the country, the history is better understood – the ideals and the hope and the heroic resistances, the betrayals and the betrayals and the sinister and incipient betrayals of the 20th century, so rich in monsters.