An elderly male in seventies, diabetic, hypertensive and asthmatic, presented with chest pain, cough, dyspnea and a chest wall swelling in left posterior axillary line for 4 months. His X-ray chest showed left sided pleural effusion. A diagnosis of possible empyema necessitans was made by the treating physician and a pigtail catheter was inserted. The drain was however non-purulent, and the swelling remained unresolved. He was therefore referred to our institute. On examination, there was a large smooth round chest wall swelling in left posterior axillary line with no skin erythema and a strong impulse on coughing. On further imaging and investigations, it was diagnosed to be a chest wall herniation of the lung. Intraoperatively, it was found that only a very thin muscle layer existed in the entire left seventh intercostal space. It was repaired with a mesh. Patient is doing well after the surgery with no recurrence.