Platypnea-orthodeoxia syndrome (POS) is a rare condition characterized by dyspnoea and deoxygenation in an upright position that is relieved by supine positioning. There are only five published accounts of it occurring post-lobectomy. We present the case of a 72-year-old male with 3 months of supposedly unexplained dyspnoea after right lower lobectomy for lung cancer who was confirmed to have POS. We highlight the importance of recognition and management as well as provide a brief summary of the pathophysiology.