Myocarditis is associated with a broad spectrum of clinical and electrocardiographic manifestations, ranging from completely asymptomatic courses to signs of myocardial infarction or cardiogenic shock. Endomyocardial biopsy is considered the gold standard for the diagnosis of myocarditis; however, in clinical practice, cardiovascular magnetic resonance (CMR) plays a leading role, being the most accurate noninvasive method for tissue characterization. We report the case of a 22-year-old patient hospitalized for acute precordial pain associated with ST-segment elevation in leads DI and aVL, mimicking acute myocardial infarction, in whom CMR led to the correct diagnosis of acute focal myocarditis.