Introduction This is a challenging case of a previously healthy patient found to be in fulminant cardiogenic shock requiring temporary advanced mechanical support. Case Report A 57-year old female with a history of depression presented with nausea and chest pain for four days. Vital signs notable for blood pressure 79/62 and electrocardiogram showed diffuse ST elevations. She was taken emergently to the catheterization laboratory, which revealed clean coronaries but elevated filling pressures (right atrial pressure 15 mmHg, pulmonary capillary wedge pressure 24 mmHg) and severe biventricular dysfunction (cardiac index 1.2 L/min/m2). Patient rapidly deteriorated, developing sustained ventricular tachycardia requiring 1 defibrillatory shock. She was intubated and placed on venoarterial extracorporeal membrane oxygenation (VA-ECMO). Transthoracic echocardiogram showed edematous myocardium with minimal pulsatility. She developed high grade AV block transitioning to complete heart block requiring a temporary pacemaker. Given concern for giant cell myocarditis, high dose steroids were initiated and she was taken for urgent endomyocardial biopsy. Pathology showed inflammation with extensive eosinophils without granulomas or giant cells. Upon further history, patient was recently initiated on aripiprazole for depression. Over the next several days, patient remained on high dose steroids for treatment of eosinophilic myocarditis with substantial clinical improvement. VA-ECMO was decannulated on day 10, and ejection fraction recovered to 55%. Summary This is a case of fulminant eosinophilic myocarditis requiring VA-ECMO where high dose steroids resulted in recovery of function; etiology thought to be initiation of aripiprazole. Eosinophilic myocarditis is a rare form of myocarditis that can result from hypersensitivity to drugs, exposure to parasites, and hyper-eosinophilic syndromes. Definitive diagnosis requires endomyocardial biopsy, and early initiation of mechanical support and high dose steroids is critical.