Pancytopenia, cholestatic jaundice, and pulmonary hypertension are rare but serious complications of thyrotoxicosis. It is uncommonly seen in patients with hyperthyroidism and may result in treatment-related dilemmas as bone marrow suppression and drug-induced liver injury are known complications of anti-thyroid treatment. We describe a case of Graves' disease presenting with all three manifestations of pancytopenia, cholestatic jaundice, and pulmonary hypertension during a relapse of thyrotoxicosis. Her anti-thyroid medications were initially withheld for fear of worsening the above manifestations, but no improvement was noted clinically or biochemically. Other lab investigations, such as hepatitis serology, autoimmune liver markers, and ultrasound, were unrevealing. Anti-thyroid medications were subsequently reinitiated after discussion with the endocrine team, with improvements in clinical condition, as well as full blood counts and liver function tests. Pulmonary hypertension also improved on her latest echocardiography. This case report intends to shed light on the atypical extrathyroidal manifestations of Grave's disease and the importance of recognition and therapy.