Sue and Sally Smith, Flying Nurses #54

The main story "Symptom of Evil" follows Sue and Sally Smith, flying nurses, as they become involved in combating a mysterious plague spreading across Europe and beyond. Dr. Michael Barlow works to develop a vaccine using Thompson's formula to strengthen people against the deadly bacteria that destroys lung tissue, while the nurses assist in administering the vaccine to the afflicted. The story includes a subplot involving a saboteur who crashes a plane and attempts to spread the plague further, but is ultimately apprehended. The issue concludes with Dr. Barlow's warning that such a plague could strike again in the future.