We present a case of a 19-year-old man with right shoulder pain lasting for several months. Abdominal imaging revealed a right adrenal mass directly invading vascular structures into the right atrium. Widespread metastatic adrenocortical carcinoma was confirmed on biopsy. He opted for palliative mitotane treatment with home hospice care. This case emphasises the importance of considering abdominal masses in the differential diagnosis of persistent right shoulder pain after common causes have been ruled out. Early diagnosis could be potentially life-saving.