A Kosovar pilgrim is on his way back to Belgrade from the Middle East. While at a bazaar, the pilgrim buys a flute from a man who is visibly ill. Upon his return to Belgrade, the pilgrim starts to show signs of illness and is transported to the city's General Hospital. His disease is initially misdiagnosed and the smallpox virus starts spreading through the hospital very quickly. Once the disease is correctly identified, the authorities attempt to subdue the outbreak by declaring martial law, enforcing quarantine and enlisting the help of the World Health Organization.