A series of messages are sent from an unknown source and leaders in government, religion and technology attempt to decipher the messages while trying covertly to use the messages to their advantage. John Tennyson, President of the United States is concerned about national security yet for Sunshine Borden, the world-class programmer, it represents a technological puzzle to be solved. In the midst of this confusion, a killer stalks victims and forces Sunshine to leave his laboratory to track him down.