A 52-year-old gentleman presented with 1-week history of severe right-sided headache associated with reduced vision in his right, amblyopic eye. Examination revealed raised intraocular pressure at 64 mm Hg. The anterior chamber (AC) was shallow and there was a dense cataract with no red reflex or fundal view. The contralateral eye had a deep anterior chamber with normal pressure and a clear lens. He was treated initially for acute angle closure glaucoma. The anterior chamber remained shallow and the intraocular pressure uncontrolled, despite maximum medical therapy. Owing to the absent fundal view and unilateral AC shallowing, further imaging was performed and a choroidal mass was found to be responsible for anterior displacement of the lens and shallowing of the angle. He went on to have an enucleation of the right eye, and histological examination confirmed the diagnosis of choroidal melanoma.