Abstract Background Fulminant myocarditis is a catastrophic disease with high mortality and complications. A viral aetiology is frequent and the implication of SARS-CoV-2 is not yet known. Case summary A 38-year-old woman who recently arrived from Spain presented with palpitations that started suddenly 3 days prior to presentation and were associated with haemodynamic instability, without dyspnoea or chest pain. We found features of myopericarditis on the electrocardiogram and severe systolic dysfunction on the echocardiogram. The chest tomography showed findings which suggested COVID-19 infection, and PCR for SARS-CoV-2 was positive. The cardiac magnetic resonance image showed Lake Louise criteria for myocarditis. The patient was treated with immunomodulatory, steroid, and immunoglobulin therapy, with a favourable clinical response. Discussion The importance of this case lies in highlighting the severe cardiac involvement in a young patient, without previous risk factors, positive for COVID-19, and the favourable response to the medical treatment given.