Melanoma is the most common form of cardiac metastases. Surgical excision has been shown to be an effective palliative measure. This requires detailed definition of cardiac anatomy in relation to the tumour. Two-dimensional (2D), three-dimensional (3D) transthoracic (TTE) and transoesophageal echocardiography (TEE), spiral computerised tomography (CT) and magnetic resonance imaging (MRI) have all been described in aiding surgical planning for excision of cardiac tumours. In this case report, 3D-TTE provided excellent anatomical definition for surgical planning of a large right atrial melanoma precluding the need for more invasive and expensive investigations.