This chapter is centred in the irruption of 15-M Movement in the Spanish political arena as one example of subterranean politics in Southern Europe. In contrast to previous cycles of mobilization (anti-globalization or anti-war, for example), the 15-M represented a milestone in relation to the subjects, repertoires and claims of the mobilization. The novelty represented by these changes connect the 15-M Movement with other experiences of subterranean politics around the world, such as the Arab Spring, Occupy and the Icelandic revolution. In all these episodes, we can find some similarities: the rejection of traditional political arrangements, civil society empowerment and its rise as as a new political actor, the claims for a deeper democracy and the strategic use of technological devices as information and coordination tools. The main aim of this chapter is to analyse how the impact of the economic crisis in the Spanish social and political context has transformed the shape and the content of social mobilization through the innovation of repertoires, the coalition actors and the frames of mobilization.