Haemoptysis and pleuritic chest pain are common presentations of cardiopulmonary disease. While a number of common disorders may explain these symptoms, occasionally unusual causes may emerge which should be considered in the differential diagnosis especially if pulmonary embolism is unlikely; so that inappropriate anticoagulation or thrombolytic therapy is avoided. We present a case of unilateral pulmonary artery agenesis, who presented with pleuritic chest pain and haemoptysis, and was initially treated as a case of pulmonary thromboembolism.