Since the late 2000s economic and immigration crises are testing the European Union (EU). Such challenges have opened up a period of radical change for the EU, among them, the Brexit referendum that will radically change EU’s geography. This turmoil is mirrored by the last European Parliament (EP) election results; extreme right- and left-wing parties succeeded in the electoral competition at the expense of their mainstream counterpart. These forces are generally labelled as ‘Eurosceptic’, even though the literature still lacks a clear-cut definition of Euroscepticism. Starting from this observation, this paper reviews the conceptual evolution of Euroscepticism, stressing its pros and cons and proposes a reconceptualization of it in terms of EU-opposition such that the objects of criticism are clearly identified as the EU-policies, the EU-elite, the EU-regime, and the EU-community. The paper applies ‘EU-opposition’ to examine empirically the activity of two ‘Eurosceptic’ parties in the EP: the Italian Five Stars Movement (FSM) and the British United Kingdom Independence Party (UKIP), using the speeches they deliver in the arena of the EP as the main source of data. From the analysis, it can be seen that UKIP and FSM are an odd couple working in the same party group in the EP, and the concept of EU-opposition is able to better disentangle UKIP and FSM’s criticism of the EU.