Adrenocortical carcinoma is a rare tumor with a dismal prognosis. In stark contrast, benign incidental adrenal lesions are detected commonly on routine abdominal imaging. We report a case of a 74-year-old man with a history of germ cell testicular carcinoma who presented with a 4.8-cm left adrenal lesion. The lesion remained stable for 8 years, at which time the patient became symptomatic from an excess of cortisol hormone. Biopsy findings confirmed adrenocortical carcinoma. We describe the presentation, clinical findings, diagnostic work-up, and follow-up of this patient and review the literature.