Cardiac sarcoidosis is a manifestation of sarcoidosis that is challenging to diagnose due to its clinical silence, but its identification is vitally important, as its consequences are potentially devastating. These consequences include conduction defects, arrhythmias, cardiomyopathy, congestive heart failure and sudden cardiac death. This case describes a 47-year-old male with a history of dilated non-ischaemic cardiomyopathy who had a delayed diagnosis of sarcoidosis with cardiac involvement after cardiac MRI proved to be inconclusive. It was later deemed to be cardiac sarcoidosis after the onset of systemic symptoms with a liver biopsy that showed sarcoid. Initial testing for cardiac sarcoidosis should include cardiac MRI. Treatment focuses on optimising heart failure therapy and placement of a biventricular implantable cardioverter defibrillator for primary prevention of sudden cardiac death. Although some studies suggest a potential benefit from glucocorticoid therapy, conclusive evidence revealing the true value of this treatment regimen has yet to be determined. © 2018, Netherlands Society of Intensive Care. All rights reserved.