A 32-year-old female presented with a stab wound to the left anterolateral chest. Lung window axial CT image through the mid-chest demonstrated an irregular, gas-filled defect along the left anterior chest wall extending to the pleural cavity (arrow). This allowed for direct communication of the pleural space with atmospheric air. Associated large left and moderate right pneumothoraces were present. Pneumothorax is likely to persist in this scenario of an open wound communicating with the atmosphere